Wednesday, September 23, 2009
High-tech Spark Plug Wires for your MINI Cooper
Interestingly, some high-tech spark plug wires can provide an alternative to the Plasma Booster to accomplish the same task of increasing the intensity of the spark produced by the spark plug and thus provide the same benefits.
The Nology company makes a set of spark plug wires that each incorporate a capacitor and separate ground connection. With this addition, the spark plug wire itself stores up the energy of the spark until it reaches a high intensity level, then releases it in a shortened burst that provides a quick, clean ignition of the fuel/air mixture.
The manufacturer claims an increase in spark intensity of over 300 percent, which measurably increases horsepower and mileage, and reduces emissions by providing more a complete burn of fuel. An added benefit is that the substitution of the high-tech spark plug wires is legal under California Air Resources Board regulations.
The Nology spark plug wires sell for $199 for the set, and can be ordered in red, blue, yellow or black for that added eye appeal in the engine compartment. Even better, they can be installed without any special tools.
Sunday, August 30, 2009
Finding a Few More Horses for your MINI Cooper
With the modifications to the engine that were suggested in Section 2, it is possible to bring the engine’s power to well over 200 horsepower. But there’s more where that came from, if you’re looking for more performance.
By getting deeper into the engine, we can bring the car up to as much as 300 horsepower, and add more torque in the rpm mid-range, adding to the car’s performance off the line, when overtaking other cars, and getting out of the corners. Horsepower-enhancing aftermarket parts include a plasma booster for spark plug performance, spark plug wires to take advantage of the stronger spark, an upgraded throttle body, a hotter cam shaft, and an improved cylinder head, as well as silicone hoses to improve reliability,.
Plasma Booster Ignition Upgrade
The intensity of the spark that is delivered to the cylinder by the spark determines how efficiently the air/fuel mixture in the cylinder will be ignited. The efficiency of the ignition in turn affects the engine’s power output, mileage, and smoothness of operation.
A simple “black box” can be added to the ignition system to achieve these benefits. Called a Plasma Booster, it is a power amplifier that increases the power of the primary and secondary spark circuit by nearly 100 percent to deliver a much “hotter” (more powerful) spark to the cylinder. A more powerful spark will ignite the air/fuel mixture more easily, and cause the mixture to burn more quickly. The result is more power from the fuel, more efficient use of fuel, and more consistent power from each individual firing for smoother engine operation.
Individual measurements before and after the addition of the plasma booster indicate an additional four horsepower from the engine, and ten percent better fuel economy. The Plasma Booster costs about $270, and can be added to the engine in just a few minutes without any special tools. As a nice plus, it is certified for use in MINIs by the California Air Resources Board because of its benefits in reduced emissions and better fuel mileage.
By getting deeper into the engine, we can bring the car up to as much as 300 horsepower, and add more torque in the rpm mid-range, adding to the car’s performance off the line, when overtaking other cars, and getting out of the corners. Horsepower-enhancing aftermarket parts include a plasma booster for spark plug performance, spark plug wires to take advantage of the stronger spark, an upgraded throttle body, a hotter cam shaft, and an improved cylinder head, as well as silicone hoses to improve reliability,.
Plasma Booster Ignition Upgrade
The intensity of the spark that is delivered to the cylinder by the spark determines how efficiently the air/fuel mixture in the cylinder will be ignited. The efficiency of the ignition in turn affects the engine’s power output, mileage, and smoothness of operation.
A simple “black box” can be added to the ignition system to achieve these benefits. Called a Plasma Booster, it is a power amplifier that increases the power of the primary and secondary spark circuit by nearly 100 percent to deliver a much “hotter” (more powerful) spark to the cylinder. A more powerful spark will ignite the air/fuel mixture more easily, and cause the mixture to burn more quickly. The result is more power from the fuel, more efficient use of fuel, and more consistent power from each individual firing for smoother engine operation.
Individual measurements before and after the addition of the plasma booster indicate an additional four horsepower from the engine, and ten percent better fuel economy. The Plasma Booster costs about $270, and can be added to the engine in just a few minutes without any special tools. As a nice plus, it is certified for use in MINIs by the California Air Resources Board because of its benefits in reduced emissions and better fuel mileage.
Wednesday, July 8, 2009
Front and Rear Strut Braces
The chassis of the MINI Cooper and Cooper S is well-designed and pretty stiff just as it comes from the factory, which is one of the reasons why your MINI felt satisfying to drive when you first drove it away from the dealer. Several reviewers have remarked that the car felt “as if it had been carved from one block of steel.”
However, as you start to drive the car harder, on track days or around the autocross cones, or just like tossing it around backroads corners, you might want to stiffen up the chassis just a bit more. This upgrade is one of the easiest in this book. It is accomplished simply by bolting a “strut brace” across the front of the car in the engine compartment, to connect the tops of the two front strut towers to one another.
The benefit of this brace is to stiffen the front of the car to reduce flex in the suspension. Where the stock MINI feels pretty stiff and strong in corners, the added strut brace makes it feel really solid so that the car turns into the corners more easily without hesitation. Of course, since the brace is visible to anyone looking in the engine compartment and is an attractive accessory, it certainly adds to the performance credibility of the car.
A stiff, well-constructed strut brace is desirable on a car that is running with low-profile, high-performance tires and especially desirable when installed in conjunction with a lowered suspension. A typical well-engineered strut brace will cost about $325, and can easily be installed by anyone with the right-sized wrenches in less than an afternoon.
Chassis stiffness becomes increasingly important as the MINI is used more often for serious autocrossing, and is an important element in suspension tuning. For this reason, many tuners also prefer to add a rear strut brace to the MINI before making other changes to the rear suspension of the car. Like the front suspension, this additional component is bolted on to the rear suspension mounts and extends across the car. A good rear strut brace can be purchased for about $200 and is easily installed.
Wednesday, June 3, 2009
MINI Cooper Anti-sway Bars to Reduce Understeer
In a front-wheel drive car, all of the steering and power comes from the front wheels. The usual result is that the typical front-wheel car has a tendency to under steer. If the car is going to fast, or turned too abruptly when entering a corner, the car will push ahead in a straight line, rather than turning to follow the direction of the front wheels.
Under steer is a good thing for the average driver turning the average corner, since the car is less likely to swerve or skid, should the driver turn the steering wheel too far or too fast. In fact, even most modern rear-wheel cars are engineered to have a little under steer.
However, since we want to get around the corners faster than the average driver, and we’re willing to invest some time and practice in learning to drive the car better, reducing that under steer seems like a good idea. Though it seems counter intuitive we can reduce the under steer on the front wheels by altering one component of the rear suspension, the rear “sway bar.”
The MINI Cooper S has a sway bar on the rear for just this purpose, to help tune the suspension. The rear sway bar keeps the rear wheels of the car more level as the car goes into corners. A sway bar—or as it is generally and more accurately referred to, an “anti-sway bar”—works by connecting the wheels on either side of the car to one another and to the chassis.
As the inside corner of the chassis begins to move up when the car rolls toward the outside of the turn, the sway bar transmits some of this motion to the outside rear corner. The net result is that the inside corner doesn’t go up as much, and the outside corner goes up more, than they would without the sway bar.
Again, think of the car as if it is balanced on a pin at its center. If we can keep the back end flatter on the turns so that the inside rear corner of the chassis doesn’t rise, less pressure is put on the outside front wheel and the car doesn’t push, or under steer as much. Instead, the rear end of the car comes around more easily. Instead of resisting the turn, the car will follow the line of the turn more easily.
However, the stock sway bar installed on the MINI represents a compromise between reducing chassis roll and affecting ride comfort in favor of ride comfort. It is also fixed in place, so it doesn’t allow any choice of response regardless of what you’ll be using your MINI for.
To improve on that situation, aftermarket suppliers have developed a stiffer rear sway bar that also has an adjustment range from harder to softer responsiveness. The original sway bar is 13mm thick, while one typical aftermarket sway bar is 16mm thick. The thicker bar is capable of transmitting more force from one side of the car to the other, helping the car stay level and balanced on tighter turns.
The typical dual-use adjustable rear sway bar kit, including the sway bar, connecting arms, bushings, and fasteners is available for about $250. The installation is straightforward, but does require putting the car on jack stands, and then removing the old bar and getting the new bar to slide in around the rear suspension components and wiring harness, so you may wish to have an experienced professional shop do the job for you.
Even heavier rear anti-sway bars are available for drivers who expect to spend a greater proportion of their time on the track or do serious autocross competition, might consider one of the heavier rear anti-sway bar that are also available. Some of these heavier bars have a more positive multi-position adjustment mechanism. The heavier rear bar is generally used in conjunction with the substitution of a heavier front roll bar in order to keep the car balanced from front to rear as well as side to side.
Under steer is a good thing for the average driver turning the average corner, since the car is less likely to swerve or skid, should the driver turn the steering wheel too far or too fast. In fact, even most modern rear-wheel cars are engineered to have a little under steer.
However, since we want to get around the corners faster than the average driver, and we’re willing to invest some time and practice in learning to drive the car better, reducing that under steer seems like a good idea. Though it seems counter intuitive we can reduce the under steer on the front wheels by altering one component of the rear suspension, the rear “sway bar.”
The MINI Cooper S has a sway bar on the rear for just this purpose, to help tune the suspension. The rear sway bar keeps the rear wheels of the car more level as the car goes into corners. A sway bar—or as it is generally and more accurately referred to, an “anti-sway bar”—works by connecting the wheels on either side of the car to one another and to the chassis.
As the inside corner of the chassis begins to move up when the car rolls toward the outside of the turn, the sway bar transmits some of this motion to the outside rear corner. The net result is that the inside corner doesn’t go up as much, and the outside corner goes up more, than they would without the sway bar.
Again, think of the car as if it is balanced on a pin at its center. If we can keep the back end flatter on the turns so that the inside rear corner of the chassis doesn’t rise, less pressure is put on the outside front wheel and the car doesn’t push, or under steer as much. Instead, the rear end of the car comes around more easily. Instead of resisting the turn, the car will follow the line of the turn more easily.
However, the stock sway bar installed on the MINI represents a compromise between reducing chassis roll and affecting ride comfort in favor of ride comfort. It is also fixed in place, so it doesn’t allow any choice of response regardless of what you’ll be using your MINI for.
To improve on that situation, aftermarket suppliers have developed a stiffer rear sway bar that also has an adjustment range from harder to softer responsiveness. The original sway bar is 13mm thick, while one typical aftermarket sway bar is 16mm thick. The thicker bar is capable of transmitting more force from one side of the car to the other, helping the car stay level and balanced on tighter turns.
The typical dual-use adjustable rear sway bar kit, including the sway bar, connecting arms, bushings, and fasteners is available for about $250. The installation is straightforward, but does require putting the car on jack stands, and then removing the old bar and getting the new bar to slide in around the rear suspension components and wiring harness, so you may wish to have an experienced professional shop do the job for you.
Even heavier rear anti-sway bars are available for drivers who expect to spend a greater proportion of their time on the track or do serious autocross competition, might consider one of the heavier rear anti-sway bar that are also available. Some of these heavier bars have a more positive multi-position adjustment mechanism. The heavier rear bar is generally used in conjunction with the substitution of a heavier front roll bar in order to keep the car balanced from front to rear as well as side to side.
Sunday, May 31, 2009
MINI Cooper Ride Height, Camber and Toe
The angles of the wheels to the pavement and to the direction of travel are two important factors in suspension behavior and consequently the way the car will handle. Because these factors have been understood for many years, they are described with the technical terms of “camber” and “toe.”
“Camber” is the angle of the wheel when compared with a vertical line, when the car is resting on its springs. If the top of the wheel leans in towards the car when the car is sitting still, we say that the wheel has “negative camber.” On the other hand, if the top of the tire leans out when the car is sitting still, that would be “positive camber.”
The camber angle is important because it will determine how much of the surface of the tire tread is in contact with the pavement when the car is going around corners. Remember we noted that the car will sway when it is turning, which will cause the inside wheel to go up and the outside wheel to go down.
Since we want as much of the tire to be in contact with the pavement as possible during the turn, we want the wheels to have a little bit of negative camber. That way, even if the weight over a particular wheel is decreased and the angle of the wheel changes as the car tilts in the corner, the full width of the tread will still be in contact with the pavement throughout the turn.
The other angle is called “toe” and measures the extent to which the front edges of the tires point in, or point out, compared to the rear edges of the tires. If the fronts of the tires are closer together than the rear, the wheels are said to “toe in;” if the rear of the tires are further apart than the front, the tires are said to “toe out.”
The extent to which the tires toe in or toe out determines how easy it is to get the car to turn. With toe-out, the car would want to go straight rather than turn, with toe-in, the car will turn more easily.
It’s important to remember that if you change the springs and shocks to lower the car, this will also change the car’s toe and camber. For this reason, most tuners will recommend that you adjust the rear toe and camber at the same time that you lower the car and change its spring rates in order to keep the car’s handling neutral and to minimize tire wear. In addition, you may wish to make changes yourself to increase the ease with which your MINI turns-in on corners.
Two methods exist to change rear toe-in: you can use a rear camber/toe kit to replace some of the rear suspension fasteners, or you can replace the stock rear control arms with adjustable control arms. The rear camber/toe kit is less expensive than the adjustable control arms, but the adjustable control arms give you a little more control of rear camber and toe and are easier to adjust.
“Camber” is the angle of the wheel when compared with a vertical line, when the car is resting on its springs. If the top of the wheel leans in towards the car when the car is sitting still, we say that the wheel has “negative camber.” On the other hand, if the top of the tire leans out when the car is sitting still, that would be “positive camber.”
The camber angle is important because it will determine how much of the surface of the tire tread is in contact with the pavement when the car is going around corners. Remember we noted that the car will sway when it is turning, which will cause the inside wheel to go up and the outside wheel to go down.
Since we want as much of the tire to be in contact with the pavement as possible during the turn, we want the wheels to have a little bit of negative camber. That way, even if the weight over a particular wheel is decreased and the angle of the wheel changes as the car tilts in the corner, the full width of the tread will still be in contact with the pavement throughout the turn.
The other angle is called “toe” and measures the extent to which the front edges of the tires point in, or point out, compared to the rear edges of the tires. If the fronts of the tires are closer together than the rear, the wheels are said to “toe in;” if the rear of the tires are further apart than the front, the tires are said to “toe out.”
The extent to which the tires toe in or toe out determines how easy it is to get the car to turn. With toe-out, the car would want to go straight rather than turn, with toe-in, the car will turn more easily.
It’s important to remember that if you change the springs and shocks to lower the car, this will also change the car’s toe and camber. For this reason, most tuners will recommend that you adjust the rear toe and camber at the same time that you lower the car and change its spring rates in order to keep the car’s handling neutral and to minimize tire wear. In addition, you may wish to make changes yourself to increase the ease with which your MINI turns-in on corners.
Two methods exist to change rear toe-in: you can use a rear camber/toe kit to replace some of the rear suspension fasteners, or you can replace the stock rear control arms with adjustable control arms. The rear camber/toe kit is less expensive than the adjustable control arms, but the adjustable control arms give you a little more control of rear camber and toe and are easier to adjust.
Tuesday, May 26, 2009
MINI Cooper Performance Spring Kit and Shock Upgrades
Two suspension components have the most direct effect on ride quality and handling performance, the springs and the shocks. The length and resilience of the springs determines how easily and how far the body will move when the wheels hit a bump or when weight is transferred in acceleration, braking, or cornering. The shock absorbers reduce the amount of rebound on the springs, helping the body to return to equilibrium after it bounces.
Let’s start with the springs. Because most car owners put more emphasis on ride comfort than on cornering and acceleration performance, most cars are equipped with fairly soft springs that are designed with a good amount of spring travel. The basis Mini Cooper would be considered in this category.
The Mini Cooper S, with its sport suspension (optional on the Mini Cooper) does use heavier (less-resilient) springs with a bit less travel, but the engineers are still assuming you just want good street handling, and aren’t going to want to go a little fast in the twisty bits or take the car on a track or autocross course.
For these purposes, a stiffer spring and lower ride height will be in order. With a stiffer spring, the car won’t cushion you as much on the bumps, but more important, it won’t sway as much on corners, or shift back and forth as much on acceleration and braking. With a shorter spring, the center of gravity will be a little lower, also reducing the amount of side-to-side or front-to-rear body roll.
Good high-performance spring kits are readily available in the aftermarket. These improved spring kits will help your car maintain its stability when starting, stopping, and turning without wallowing around. These kits won’t make your car ride so rough that your passengers will complain, but they will definitely increase the predictability of the car in the corners and help reduce your lap times. A typical upgraded spring kit sells for less than $250.
While most of the good performance spring kits will work with the original equipment shocks, you might want to consider upgrading your shock absorbers at the same time. The shock absorbers work together with your springs so that the car doesn’t just bounce up and down and up and down every time it sways or hits a bump.
Actually, the term “shock absorber” isn’t quite accurate, since the springs actually absorb the shocks from uneven road surfaces, while the shock absorbers help counter the effect of the springs. The English call them “dampers” which is a more accurate term.
The shock absorbers in the MINI are long tubes that are installed between the wheel and the chassis in parallel with the springs. Inside the outer tube is a piston with a special valve that allows fluid to move from the main tube into the piston as the shock absorber compresses and then move back into the main tube at a slower rate when the shock absorber extends.
The shock absorber works by compressing easily when the spring compresses, but then reducing the rate at which the spring expands. So, instead of continuing to oscillate up and down as it would if only the spring were in between the chassis and wheel, the chassis comes back to a neutral position after only one or two movements.
Like original equipment springs, original equipment shocks are designed to do their job with emphasis on comfort, rather than performance. They damp the spring movement just enough to avoid making passengers seasick, but not enough to give a harder ride. To improve your handling, you’ll want even less oscillation so that the car will return to a neutral position more quickly.
By installing performance shocks, you still get some springing action to absorb the bumps and weight changes, but the car will move less and return to neutral more quickly after acceleration or braking, or in between corners. A set of performance shocks designed specifically for the MINI, such as the one by Koni, is a good complement to shorter, stiffer performance springs. One MINI aftermarket catalog offers the Koni shocks for front and rear for a total of about $690, or the combination of performance springs and Koni shocks for a total of $875.
Spax makes a set of “coil-over” shocks that are an alternative to replacing the springs and shocks separately. With this kit, performance springs are wrapped around the shocks, hence the name, and the combined spring and shock is mounted after removing both the stock spring and stock shock at each corner. This alternative is more expensive that installing springs and shocks separately, typically selling for about $1300.
Coil-over kits can certainly be used to improve the handling on street cars. However, they are more likely to be installed by owners who expect to use their MINI frequently on the track or autocross course, since they are available in different spring rates and do offer the means to adjust ride height at each corner.
Different spring rates will be appropriate, depending on the experience of the driver and the frequency with which the car will be used in competition. Springs that are closer to stock firmness will be appropriate for the person who doesn’t compete too often, and also wants to use the car for street use. On the other hand, if the MINI is only going to be used for competition and the driver is quite experienced, the preference will be for a much firmer spring.
By adjusting the ride height at each corner, the owner can balance corner weights to compensate for other changes that have been made in the car, since balance is very important in tuning the car’s handling for the race track.
Let’s start with the springs. Because most car owners put more emphasis on ride comfort than on cornering and acceleration performance, most cars are equipped with fairly soft springs that are designed with a good amount of spring travel. The basis Mini Cooper would be considered in this category.
The Mini Cooper S, with its sport suspension (optional on the Mini Cooper) does use heavier (less-resilient) springs with a bit less travel, but the engineers are still assuming you just want good street handling, and aren’t going to want to go a little fast in the twisty bits or take the car on a track or autocross course.
For these purposes, a stiffer spring and lower ride height will be in order. With a stiffer spring, the car won’t cushion you as much on the bumps, but more important, it won’t sway as much on corners, or shift back and forth as much on acceleration and braking. With a shorter spring, the center of gravity will be a little lower, also reducing the amount of side-to-side or front-to-rear body roll.
Good high-performance spring kits are readily available in the aftermarket. These improved spring kits will help your car maintain its stability when starting, stopping, and turning without wallowing around. These kits won’t make your car ride so rough that your passengers will complain, but they will definitely increase the predictability of the car in the corners and help reduce your lap times. A typical upgraded spring kit sells for less than $250.
While most of the good performance spring kits will work with the original equipment shocks, you might want to consider upgrading your shock absorbers at the same time. The shock absorbers work together with your springs so that the car doesn’t just bounce up and down and up and down every time it sways or hits a bump.
Actually, the term “shock absorber” isn’t quite accurate, since the springs actually absorb the shocks from uneven road surfaces, while the shock absorbers help counter the effect of the springs. The English call them “dampers” which is a more accurate term.
The shock absorbers in the MINI are long tubes that are installed between the wheel and the chassis in parallel with the springs. Inside the outer tube is a piston with a special valve that allows fluid to move from the main tube into the piston as the shock absorber compresses and then move back into the main tube at a slower rate when the shock absorber extends.
The shock absorber works by compressing easily when the spring compresses, but then reducing the rate at which the spring expands. So, instead of continuing to oscillate up and down as it would if only the spring were in between the chassis and wheel, the chassis comes back to a neutral position after only one or two movements.
Like original equipment springs, original equipment shocks are designed to do their job with emphasis on comfort, rather than performance. They damp the spring movement just enough to avoid making passengers seasick, but not enough to give a harder ride. To improve your handling, you’ll want even less oscillation so that the car will return to a neutral position more quickly.
By installing performance shocks, you still get some springing action to absorb the bumps and weight changes, but the car will move less and return to neutral more quickly after acceleration or braking, or in between corners. A set of performance shocks designed specifically for the MINI, such as the one by Koni, is a good complement to shorter, stiffer performance springs. One MINI aftermarket catalog offers the Koni shocks for front and rear for a total of about $690, or the combination of performance springs and Koni shocks for a total of $875.
Spax makes a set of “coil-over” shocks that are an alternative to replacing the springs and shocks separately. With this kit, performance springs are wrapped around the shocks, hence the name, and the combined spring and shock is mounted after removing both the stock spring and stock shock at each corner. This alternative is more expensive that installing springs and shocks separately, typically selling for about $1300.
Coil-over kits can certainly be used to improve the handling on street cars. However, they are more likely to be installed by owners who expect to use their MINI frequently on the track or autocross course, since they are available in different spring rates and do offer the means to adjust ride height at each corner.
Different spring rates will be appropriate, depending on the experience of the driver and the frequency with which the car will be used in competition. Springs that are closer to stock firmness will be appropriate for the person who doesn’t compete too often, and also wants to use the car for street use. On the other hand, if the MINI is only going to be used for competition and the driver is quite experienced, the preference will be for a much firmer spring.
By adjusting the ride height at each corner, the owner can balance corner weights to compensate for other changes that have been made in the car, since balance is very important in tuning the car’s handling for the race track.
Tuesday, April 14, 2009
Better Handling for Road, Track or Autocross in a MINI Cooper
In the second section of this book, we were particularly complimentary regarding the MINI Cooper's stock suspension, noting that it will reward a good driver and can be well down the priority list of things to work on for improved performance. Now, with a few days of track time under your belt, or maybe a day or two out on the autocross course, and lots of corners that you have been practicing to go around just right, you may be ready to consider tweaking the suspension a bit for better handling performance.
Once again we’re back to trade-offs. For the average driver, with average passengers, the ability of the car to absorb bumps without rattling the dentures of gran’pa in the back seat is at least as important as how fast the car will get around corners.
As a result, when designing the shocks, springs, and suspension on any car, engineeers are going to err at least slightly on the side of a soft ride. The trade-off is that the car will lean more when going around corners.In moderate corners, as the car leans, that weight transfer is going to take weight off one of the powered wheels, and push the other wheel more firmly against the pavement, causing it to scrub a little bit. Push that car too hard through a corner and that lean could even turn into a roll. Either way, you’re not going to go around the corner as fast as you would if the car didn’t lean so much.
In the interests of improving your potential to get around corners, you may want to think about changing the trade-off, so that the car may not ride as softly going over bumps, but it will lean less going around corners. To do this, you’ll want to consider replacing the springs, upgrading the shocks, adding a rear sway bar, and changing the rear control arms.Once again we’re back to trade-offs. For the average driver, with average passengers, the ability of the car to absorb bumps without rattling the dentures of gran’pa in the back seat is at least as important as how fast the car will get around corners.
As a result, when designing the shocks, springs, and suspension on any car, engineeers are going to err at least slightly on the side of a soft ride. The trade-off is that the car will lean more when going around corners.In moderate corners, as the car leans, that weight transfer is going to take weight off one of the powered wheels, and push the other wheel more firmly against the pavement, causing it to scrub a little bit. Push that car too hard through a corner and that lean could even turn into a roll. Either way, you’re not going to go around the corner as fast as you would if the car didn’t lean so much.
Each of these suspension modifications can be installed separately, if your budget is limited, and they can be installed in the order in which they’re discussed. If you can swing the expense, you can save money and gain maximum improvements in handling, by installing all the components at the same time.
Thursday, April 2, 2009
MINI Cooper Lightweight Flywheel
If you are considering changing the clutch and your budget will tolerate the added cost, you may also wish to change the flywheel at the same time.
The flywheel on an automobile engine is a large disc at the rear of the engine that has a great deal to do with how smooth the engine runs. It is fastened to the end of the crankshaft, the shaft that is rotated as the pistons go up and down inside the cylinders. The momentum of the flywheel is used in order to smooth out the operation of the engine as its speed changes.
As the engine builds up speed, part of its energy is used to spin the flywheel, which being large and heavy, requires some time to build up momentum. Once the flywheel is spinning, that momentum keeps it spinning for a short time, even after you let off on the gas and the engine is no longer producing as much power. The flywheel keeps the engine from speeding up or slowing down too abruptly, which in turn smooths out the car’s changes in speed, keeping your passengers more comfortable.
On most brands of automobile, the flywheel consists of a single metal disc with a center hub that clamps to the crankshaft. It also has a toothed gear around the outside edge against which the starter gears engage when you press the starter button.
For smoother performance in engine and clutch operation on the MINI Cooper S, BMW engineers have taken the basic flywheel design one step further. The MCS flywheel is what is known as a “dual-mass” flywheel. Instead of using just one disc, this flywheel consists of two discs with a spring mechanism in between. The spring mechanism allows the disc fastened to the crankshaft to rotate as much as 70 degrees, almost a quarter of a turn, before the disc that engages the clutch is put into motion.
This design permits smoother clutch engagement, and also damps out much of the noise and vibration that is generated between the clutch and flywheel. Here again, the designers have balanced comfort against performance, giving up a little performance to get a little comfort, which the average driver and passenger wants.
However, if you want to push the balance a little towards performance, and are willing to live with a bit more noise, especially when the car is not in gear, you can replace the stock flywheel with a lightweight single-disc flywheel. An aftermarket aluminum flywheel can weigh less than half the weight of the stock flywheel without risking engine longevity.
With a lighter flywheel, you’ll get quicker acceleration and deceleration. These are two positive benefits if you’re trying to get around an autocross course or track as quickly as possible, since best time of day will go the the car that can speed up on the straightaways faster, and slow down into the turns more quickly.
Since it seems as if every drivetrain modification in the typical tuner catalog promises increased horsepower, we should probably make sure that you understand that lightening the flywheel does not increase horsepower, since it doesn’t alter the engine operation. It simply increases the responsiveness of the car when you get on and off the throttle. Many drivers will mistake this responsiveness for added horsepower. The lightened flywheel will help reduce your lap times, and make driving more fun, but it won’t increase horsepower, grow hair on that bald spot, or perform any similar miracles.
A lightweight aluminum flywheel will cost approximately $500. Since it is necessary to remove the clutch to replace the flywheel, if you’re already substituting a high-performance clutch, it is considerably less expensive in the long run to change the flywheel at the same time.
Thursday, March 26, 2009
Performance Clutch Kit
The clutch is that essential little piece of friction material that connects all that power being generated by the engine to the transmission and driveshaft that make the wheels go round. It’s surprising to think that all that power is transmitted through two discs pressed up against one another: no chains, no gears, just pressure and friction.
On the other hand, if the car didn’t have a clutch, there would be no way of disconnecting the running engine from the transmission so that you could change gears or, for that matter, stop the car while keeping the engine going. For a quick primer in how a clutch operates, check out www.howstuffworks.com/clutch.htm.
Yet, it’s the contact between the two plates, the springs that hold the plates together, the friction material on the clutch plate, and the release mechanism that pulls the plates apart that can make all the difference. These parts determine how quickly and smoothly the plates separate to allow a quick gear change, and how quickly and tightly the plates go back together to put the power back to the wheels. And that speed and efficiency makes a big difference in performance and driving sensations when the car is pushed close to its limits on the track, in and out of the cones on an autocross course or on the curves of a scenic backroad.
Like many other performance parts, clutches represent trade-offs between price and performance, and between speed and comfort. The clutch with which the car is equipped from the factory is a good component, but is built to a budget. More important, it is built with the average (or below-average) driver in mind, so its design and choice of materials err in favor of comfort and longevity, rather than performance and speed.
If you’re thinking about using your MINI Cooper or Cooper S in a more enthusiastic way than that average driver, you may be willing to pay spend some money to improve the performance of your clutch. Of course, you should also be willing to accept the need to be more quick and precise with your gear changes than that average driver so that you don’t start off, or go through gear changes, in neck-snapping fits and starts.
If you are, a performance clutch kit may be your ticket. But it isn’t a simple, “either-or” choice, since there are several levels of upgrade available. One typical catalog, for example, offers a “high-performance street kit,” a “casual autocross kit,” a “casual drag race kit,” a “race kit” and a top-of-the-line “high performance flywheel/clutch system.”
Choosing the one that’s right for you is largely determined by what you want to do with your car. Aside from the top-of-the-line system, the prices aren’t significantly different for various applications. These kits sell in the range of $400 to $600, not including installation.
All of the kits consist of the clutch disc that is pressed against the flywheel when the clutch is engaged, the pressure plate that pushes the clutch against the flywheel, the throwout bearing which pushes the clutch disc away from the flywheel when the clutch pedal is depressed, and the alignment tool needed to install the parts.
It is the type of friction material that makes the difference among the clutches designed for different applications. In the “street kit” level, a steel-backed woven organic material is used, that allows a small amount of slippage before hooking up. This slippage, though less than that of the stock clutch disc, will smooth out the clutch engagement when starting off from a stop. Allowing the clutch to slip slightly can be important in situations such as starting from a stop on a hill.
The higher performance clutches will engage more positively, since the intention is to get off from a stop as quickly as possible, and spend as little time as possible with the flywheel spinning but not connected to the transmission while shifting gears. On these clutches, kevlar, carbon or ceramic materials are used on the clutch disc, which allow for less slippage than stock disc materials as the clutch is engaged.
At the level of performance and activities being discussed in this chapter, where you’re using the car as a daily driver, but taking it out occasionally for a track day, autocross, or long-distance tour, you will probably be quite happy with a high-performance street kit. The organic disc material will provide more grip and quicker engagement and disengagement than the stock clutch, but still allows a little slippage.
On the other hand, if the car didn’t have a clutch, there would be no way of disconnecting the running engine from the transmission so that you could change gears or, for that matter, stop the car while keeping the engine going. For a quick primer in how a clutch operates, check out www.howstuffworks.com/clutch.htm.
Yet, it’s the contact between the two plates, the springs that hold the plates together, the friction material on the clutch plate, and the release mechanism that pulls the plates apart that can make all the difference. These parts determine how quickly and smoothly the plates separate to allow a quick gear change, and how quickly and tightly the plates go back together to put the power back to the wheels. And that speed and efficiency makes a big difference in performance and driving sensations when the car is pushed close to its limits on the track, in and out of the cones on an autocross course or on the curves of a scenic backroad.
Like many other performance parts, clutches represent trade-offs between price and performance, and between speed and comfort. The clutch with which the car is equipped from the factory is a good component, but is built to a budget. More important, it is built with the average (or below-average) driver in mind, so its design and choice of materials err in favor of comfort and longevity, rather than performance and speed.
If you’re thinking about using your MINI Cooper or Cooper S in a more enthusiastic way than that average driver, you may be willing to pay spend some money to improve the performance of your clutch. Of course, you should also be willing to accept the need to be more quick and precise with your gear changes than that average driver so that you don’t start off, or go through gear changes, in neck-snapping fits and starts.
If you are, a performance clutch kit may be your ticket. But it isn’t a simple, “either-or” choice, since there are several levels of upgrade available. One typical catalog, for example, offers a “high-performance street kit,” a “casual autocross kit,” a “casual drag race kit,” a “race kit” and a top-of-the-line “high performance flywheel/clutch system.”
Choosing the one that’s right for you is largely determined by what you want to do with your car. Aside from the top-of-the-line system, the prices aren’t significantly different for various applications. These kits sell in the range of $400 to $600, not including installation.
All of the kits consist of the clutch disc that is pressed against the flywheel when the clutch is engaged, the pressure plate that pushes the clutch against the flywheel, the throwout bearing which pushes the clutch disc away from the flywheel when the clutch pedal is depressed, and the alignment tool needed to install the parts.
It is the type of friction material that makes the difference among the clutches designed for different applications. In the “street kit” level, a steel-backed woven organic material is used, that allows a small amount of slippage before hooking up. This slippage, though less than that of the stock clutch disc, will smooth out the clutch engagement when starting off from a stop. Allowing the clutch to slip slightly can be important in situations such as starting from a stop on a hill.
The higher performance clutches will engage more positively, since the intention is to get off from a stop as quickly as possible, and spend as little time as possible with the flywheel spinning but not connected to the transmission while shifting gears. On these clutches, kevlar, carbon or ceramic materials are used on the clutch disc, which allow for less slippage than stock disc materials as the clutch is engaged.
At the level of performance and activities being discussed in this chapter, where you’re using the car as a daily driver, but taking it out occasionally for a track day, autocross, or long-distance tour, you will probably be quite happy with a high-performance street kit. The organic disc material will provide more grip and quicker engagement and disengagement than the stock clutch, but still allows a little slippage.
Sunday, March 22, 2009
Short Shifter the MINI Cooper for Shifting Satisfaction
Short Shifter for Shifting Satisfaction
One of the most satisfying aspects of performance driving is to run the car up through the gears with a series of crisp flicks of the shift lever. In the stock MINI, the transmission and gear shift linkage are designed to make this process fairly seamless, but the “throws” — the distance the shift lever has to be moved between gears — are fairly long.
The problem here is that while you are moving the shift lever from one gear position to the next, you have to have the clutch pedal in and the clutch disengaged. That means that the car is simply coasting. And coasting means you’re wasting time.
If it was possible to shorten the distance that your hand has to move to shift gears, then the time lost coasting between gears would be reduced. And that means you can get back on the throttle sooner during each shift of gears. It also means that your “heel and toe” will work more effectively on downshifts, because there will be a shorter period of time between blipping the throttle and actually changing down into the next lower gear.
Reducing the shifter distance is a straightforward improvement, taking advantage of the principles of leverage. All that is required is installation of an extension on the lower end of the shift lever. This changes the leverage between the shift lever and the rod that connects it to the transmission, so that you don’t have to move your hand as far to make the gear change. This modified gear lever is often called a “short shifter.”
A “short shift kit” to make the change is available from aftermarket suppliers for approximately $90. This kit consists of the extension to the shift lever and a modified dust cover plate for the box that encloses the shift lever mechanism under the car.
Working underneath the car, the mechanic removes the original dust cover plate, disconnects the shift rod, adds the extension, makes some alterations to the shift lever case, and then installs the new dust cover plate. The mechanical work is not complicated, but it does involve raising the car, removing the exhaust system and modifying the the case. Most owner will prefer to leave the work to an experienced modification shop.
One of the most satisfying aspects of performance driving is to run the car up through the gears with a series of crisp flicks of the shift lever. In the stock MINI, the transmission and gear shift linkage are designed to make this process fairly seamless, but the “throws” — the distance the shift lever has to be moved between gears — are fairly long.
The problem here is that while you are moving the shift lever from one gear position to the next, you have to have the clutch pedal in and the clutch disengaged. That means that the car is simply coasting. And coasting means you’re wasting time.
If it was possible to shorten the distance that your hand has to move to shift gears, then the time lost coasting between gears would be reduced. And that means you can get back on the throttle sooner during each shift of gears. It also means that your “heel and toe” will work more effectively on downshifts, because there will be a shorter period of time between blipping the throttle and actually changing down into the next lower gear.
Reducing the shifter distance is a straightforward improvement, taking advantage of the principles of leverage. All that is required is installation of an extension on the lower end of the shift lever. This changes the leverage between the shift lever and the rod that connects it to the transmission, so that you don’t have to move your hand as far to make the gear change. This modified gear lever is often called a “short shifter.”
A “short shift kit” to make the change is available from aftermarket suppliers for approximately $90. This kit consists of the extension to the shift lever and a modified dust cover plate for the box that encloses the shift lever mechanism under the car.
Working underneath the car, the mechanic removes the original dust cover plate, disconnects the shift rod, adds the extension, makes some alterations to the shift lever case, and then installs the new dust cover plate. The mechanical work is not complicated, but it does involve raising the car, removing the exhaust system and modifying the the case. Most owner will prefer to leave the work to an experienced modification shop.
Sunday, March 1, 2009
Getting More Bite from Your MINI Cooper Brakes
If you’ve had the chance to spend a day out on the track, we suspect that towards the end of the day you were starting to smell a fragrance that was new to you: the odor of hot brakes. You may also have noticed that you were having to push harder on the brake pedal and your car was taking longer to slow down. And then there was the fine dirty dust that was coating those slick new wheels.
What you were learning was that brake pads intended for street use just don’t cut it for a hard day of track use. So if you’re thinking seriously about going back out on the track, and are already thinking about how you could go faster on some of the corners, it’s time to switch to performance brake pads and to consider upgrading your brake rotors.
Upgraded Brake Pads
Switching brake pads is not an expensive or technically difficult chore. If you’re thinking about going faster, then you’ll want to be able to stop more quickly, and that means new brake pads.
Disc brakes seem like simple devices. When the brake pedal is pressed, a “master cylinder” behind the pedal forces brake fluid through the brake lines to the “slave cylinders” on each wheel. The slave cylinders in turn push against the backs of brake pads in the brake calipers on each wheel and these pads push against both sides of the brake discs (discs also are often referred to as “rotors”).
Since the brake rotors are connected directly to the wheels, the friction created by the pressure of the pads against the rotors slows down the wheel, causing the car to slow down. The rubbing of the brake pads against the rotors generates heat as a byproduct of the process.
How well the brakes work, especially over a long period when they are being used frequently—such as descending a long hill on curving roads or when speed changes from very fast to very slow take place frequently, such as in racing—depends on two factors. The first is the co-efficient of friction between the material in the disc and the material in the pad. The second is the ability of the pad to maintain that friction as the heat generated by the friction causes the rotor to heat up.
Both of these factors are determined by the material with which the brake pad is made. Brake pads are made of a variety of different materials, including organic, metallic, and ceramic materials, each with its own co-efficient of friction and ability to function effectively at varying temperatures.
On the street, you don’t use your brakes very hard or very frequently. As a result, brake pads designed for street use are typically made of materials that are softer and have lower co-efficients of friction so that they will slow the car down gradually and progressively, rather than an abrupt or grabby manner.
However, when you’re driving in a spirited manner at a track day or on the autocross course, you don’t want to slow down gradually. If you’re going to get good lap times on the autocross course, or be able to really drive at higher speeds on the track, you want the car to slow down in as short a distance as possible, something that the standard street pads aren’t really designed to do.
Also, if you put to the brakes to hard, continuous use—on a long section of curving roads, on an autocross course, or most definitely at a track day—the softer material on the street pads will become less effective in slowing the car down. As heat builds up in the disc from continuous use, the co-efficient of friction between the pad and the rotor decreases. In practical terms, that means you have to exert more and more pressure on the pedal to get the car to slow down, and stopping distances become longer and longer.
The easiest way to correct this is to substitute brake pads that have a higher co-efficient of friction and can stand up to heat for longer period of time. To meet these objectives, there are a wide range of alternative pads that you might buy. You can buy pads that are designed specifically for high-performance racing, and several gradations below that level.
Here, you don’t want to go overboard. A set of pads that would be perfect for a driver at the national championships is not what you want to put on your car for the occasional track day. That additional bite that will slow a race car down quickly from high speeds would throw your maiden aunt into her seat belts, something she probably wouldn’t appreciate.
In addition, racing brake pads that function very effectively at high temperatures don’t work well when they are cold. These types of pads are excellent for racing conditions where they can be heated up before being used hard, but are totally unsafe for daily driving where brakes are used more infrequently and are almost never heated to any degree.
The good thing is that there pads available for all levels of use. if you do anticipate the occasional high-spirited outing, but normally use the car for more typical purposes, you can easily find an all-around brake pad that will perform better on the track or autocross course, give you better responsiveness on the road, but will still be safe and comfortable for daily use.
You want one that will give a better “bite” than stock street pads and handle higher temperatures, but not be a full-on race pad. When selecting the pad, look at three factors: co-efficient of friction or “bite,” ability to function at high temperatures, and price.
One example of a good compromise is the “Greenstuff” brake pad set made by EBC, which produces adequate stopping power at lower temperatures than stock pads, thus reducing heat build-up, and will function effectively up to 800 degrees F. A side-benefit of these slightly harder pads is that they’ll generate less brake dust under normal or extended usage, so that your wheels don’t have to be cleaned as often. A set of these for the MINI will cost around $90 for the front pair and $80 for the rear pair.
Drilled and Slotted Rotors
Heat that causes deterioration of the brakes is not just a factor of the brake pads; it is also generated by the brake rotors, or brake discs, against which the brake pads rub. Build-up of brake pad residue on the rotors is a second source of deterioration of brake performance during a series of sessions during a track day.
Excellent replacement brake rotors are available that do a much better job of solving all of these problems than the original brake rotors with which the car comes equipped. Two different styles are good examples of the alternatives available to you, at two different price levels.
At the basic cost level, you can improve your brakes by substituting drilled and slotted single-disc rotors for the stock rotors on your MINI. Drilled brake rotors are permitted in BMWCCA spec class racing. These rotors are drilled through their surface at a number of points across the area where the pads rub against the rotor, and also have slots machined into them that extend diagonally across the disc from the inside to the outside.
Drilling the rotors has a major advantage in giving heat a place to dissipate, thus reducing the amount of heat build-up in spirited driving. Drilling as the secondary advantage of reducing the weight of the rotors, thus reducing the unsprung weight that has to be spun up and moved around when the car is in motion.
The grooves also help dissipate the heat from the rotors by creating a draft effect across the surface of the disc. In addition, they provide a channel through which the dust generated as the brake pads rub against the rotors can be removed from underneath the pads. By keeping the pads clean, the grooves increase the frictional efficiency of the brakes.
The increased efficiency and reduction in heat build-up can make a big difference in maintaining your brake performance throughout an entire track day, and they help make sure that the brakes are as good on your last run of the day as on the first. In addition, they are inexpensive insurance to keep your brakes operating efficiently on the road over a long day of enthusiastic back-roads touring as well as on steep hill descents.
A good quality pair of drilled and slotted front rotors is available from catalog suppliers for about $180, and the slightly smaller rotors that fit the rear brakes is available for about $150. Installation of these rotors is a bolt-on, bolt-off affair.
If you’re a little more serious about improving your brake performance, but don’t want to replace your entire brake system to get more brake surface area, there is a slightly pricier option. You might wish instead to consider a high-quality pair of double-surface cross-drilled brake rotors, such as those manufactured by Brembo Brakes.
In addition to having the advantages of weight reduction, heat reduction, and pad cleaning offered by other cross-drilled brakes, the Brembo rotors are constructed in a different way than standard single-plate rotors.
Like the brake rotors on all professional race cars in NASCAR, ALMS, and Formula 1, these rotors are constructed of two layers of metal. The two metal plates of the rotors are joined by braces in between the surfaces that create openings along the edge of the rotor.
The openings created by the cross-drilling, and the openings on the edges of the rotor work together to help ventilate and cool the brake rotors. In addition, this construction strengthens the rigidity of the rotor, reducing the chance that the rotor will become distorted under heavy use.
These Brembo rotors have an attractive gold anti-corrosion finish that helps eliminate surface rust that can interfere with brake performance. The gold rotors also enhance the look of any road wheels, and give the MINI a more aggressive look. They are available for about $320 for the front brakes and about 4220 for the rear brakes. They are quite simple to install in a bolt-off, bolt-on operation and fit all standard MINI wheels.
What you were learning was that brake pads intended for street use just don’t cut it for a hard day of track use. So if you’re thinking seriously about going back out on the track, and are already thinking about how you could go faster on some of the corners, it’s time to switch to performance brake pads and to consider upgrading your brake rotors.
Upgraded Brake Pads
Switching brake pads is not an expensive or technically difficult chore. If you’re thinking about going faster, then you’ll want to be able to stop more quickly, and that means new brake pads.
Disc brakes seem like simple devices. When the brake pedal is pressed, a “master cylinder” behind the pedal forces brake fluid through the brake lines to the “slave cylinders” on each wheel. The slave cylinders in turn push against the backs of brake pads in the brake calipers on each wheel and these pads push against both sides of the brake discs (discs also are often referred to as “rotors”).
Since the brake rotors are connected directly to the wheels, the friction created by the pressure of the pads against the rotors slows down the wheel, causing the car to slow down. The rubbing of the brake pads against the rotors generates heat as a byproduct of the process.
How well the brakes work, especially over a long period when they are being used frequently—such as descending a long hill on curving roads or when speed changes from very fast to very slow take place frequently, such as in racing—depends on two factors. The first is the co-efficient of friction between the material in the disc and the material in the pad. The second is the ability of the pad to maintain that friction as the heat generated by the friction causes the rotor to heat up.
Both of these factors are determined by the material with which the brake pad is made. Brake pads are made of a variety of different materials, including organic, metallic, and ceramic materials, each with its own co-efficient of friction and ability to function effectively at varying temperatures.
On the street, you don’t use your brakes very hard or very frequently. As a result, brake pads designed for street use are typically made of materials that are softer and have lower co-efficients of friction so that they will slow the car down gradually and progressively, rather than an abrupt or grabby manner.
However, when you’re driving in a spirited manner at a track day or on the autocross course, you don’t want to slow down gradually. If you’re going to get good lap times on the autocross course, or be able to really drive at higher speeds on the track, you want the car to slow down in as short a distance as possible, something that the standard street pads aren’t really designed to do.
Also, if you put to the brakes to hard, continuous use—on a long section of curving roads, on an autocross course, or most definitely at a track day—the softer material on the street pads will become less effective in slowing the car down. As heat builds up in the disc from continuous use, the co-efficient of friction between the pad and the rotor decreases. In practical terms, that means you have to exert more and more pressure on the pedal to get the car to slow down, and stopping distances become longer and longer.
The easiest way to correct this is to substitute brake pads that have a higher co-efficient of friction and can stand up to heat for longer period of time. To meet these objectives, there are a wide range of alternative pads that you might buy. You can buy pads that are designed specifically for high-performance racing, and several gradations below that level.
Here, you don’t want to go overboard. A set of pads that would be perfect for a driver at the national championships is not what you want to put on your car for the occasional track day. That additional bite that will slow a race car down quickly from high speeds would throw your maiden aunt into her seat belts, something she probably wouldn’t appreciate.
In addition, racing brake pads that function very effectively at high temperatures don’t work well when they are cold. These types of pads are excellent for racing conditions where they can be heated up before being used hard, but are totally unsafe for daily driving where brakes are used more infrequently and are almost never heated to any degree.
The good thing is that there pads available for all levels of use. if you do anticipate the occasional high-spirited outing, but normally use the car for more typical purposes, you can easily find an all-around brake pad that will perform better on the track or autocross course, give you better responsiveness on the road, but will still be safe and comfortable for daily use.
You want one that will give a better “bite” than stock street pads and handle higher temperatures, but not be a full-on race pad. When selecting the pad, look at three factors: co-efficient of friction or “bite,” ability to function at high temperatures, and price.
One example of a good compromise is the “Greenstuff” brake pad set made by EBC, which produces adequate stopping power at lower temperatures than stock pads, thus reducing heat build-up, and will function effectively up to 800 degrees F. A side-benefit of these slightly harder pads is that they’ll generate less brake dust under normal or extended usage, so that your wheels don’t have to be cleaned as often. A set of these for the MINI will cost around $90 for the front pair and $80 for the rear pair.
Drilled and Slotted Rotors
Heat that causes deterioration of the brakes is not just a factor of the brake pads; it is also generated by the brake rotors, or brake discs, against which the brake pads rub. Build-up of brake pad residue on the rotors is a second source of deterioration of brake performance during a series of sessions during a track day.
Excellent replacement brake rotors are available that do a much better job of solving all of these problems than the original brake rotors with which the car comes equipped. Two different styles are good examples of the alternatives available to you, at two different price levels.
At the basic cost level, you can improve your brakes by substituting drilled and slotted single-disc rotors for the stock rotors on your MINI. Drilled brake rotors are permitted in BMWCCA spec class racing. These rotors are drilled through their surface at a number of points across the area where the pads rub against the rotor, and also have slots machined into them that extend diagonally across the disc from the inside to the outside.
Drilling the rotors has a major advantage in giving heat a place to dissipate, thus reducing the amount of heat build-up in spirited driving. Drilling as the secondary advantage of reducing the weight of the rotors, thus reducing the unsprung weight that has to be spun up and moved around when the car is in motion.
The grooves also help dissipate the heat from the rotors by creating a draft effect across the surface of the disc. In addition, they provide a channel through which the dust generated as the brake pads rub against the rotors can be removed from underneath the pads. By keeping the pads clean, the grooves increase the frictional efficiency of the brakes.
The increased efficiency and reduction in heat build-up can make a big difference in maintaining your brake performance throughout an entire track day, and they help make sure that the brakes are as good on your last run of the day as on the first. In addition, they are inexpensive insurance to keep your brakes operating efficiently on the road over a long day of enthusiastic back-roads touring as well as on steep hill descents.
A good quality pair of drilled and slotted front rotors is available from catalog suppliers for about $180, and the slightly smaller rotors that fit the rear brakes is available for about $150. Installation of these rotors is a bolt-on, bolt-off affair.
If you’re a little more serious about improving your brake performance, but don’t want to replace your entire brake system to get more brake surface area, there is a slightly pricier option. You might wish instead to consider a high-quality pair of double-surface cross-drilled brake rotors, such as those manufactured by Brembo Brakes.
In addition to having the advantages of weight reduction, heat reduction, and pad cleaning offered by other cross-drilled brakes, the Brembo rotors are constructed in a different way than standard single-plate rotors.
Like the brake rotors on all professional race cars in NASCAR, ALMS, and Formula 1, these rotors are constructed of two layers of metal. The two metal plates of the rotors are joined by braces in between the surfaces that create openings along the edge of the rotor.
The openings created by the cross-drilling, and the openings on the edges of the rotor work together to help ventilate and cool the brake rotors. In addition, this construction strengthens the rigidity of the rotor, reducing the chance that the rotor will become distorted under heavy use.
These Brembo rotors have an attractive gold anti-corrosion finish that helps eliminate surface rust that can interfere with brake performance. The gold rotors also enhance the look of any road wheels, and give the MINI a more aggressive look. They are available for about $320 for the front brakes and about 4220 for the rear brakes. They are quite simple to install in a bolt-off, bolt-on operation and fit all standard MINI wheels.
Wednesday, February 25, 2009
Making Your MINI Cooper More Responsive
In an earlier section of this book, we suggested that you could enhance the performance of your MINI Cooper by making a few changes to the engine, upgrading the air intake, supercharger, ECU, and exhaust. We think that any MINI Cooper on the street can benefit from the added horsepower and more satisfying engine response that these upgrades will supply.
In this chapter, we’re assuming that as you try out the various driving activities available to MINI Cooper enthusiasts—touring and rallying, track days, or autocross—that you will start to think about making some additional improvements to your MINI Cooper. As your driving skills increase, you’ll discover some limits to the street-stock car that can easily be addressed with readily available substitute parts and accessories.
Let’s consider them in the order that we think makes sense. As you take a more active interest in your driving, and become more conscious of the car’s behavior, you’ll be ready to appreciate more responsiveness. Responsiveness is found in the feeling when you step on the brakes, shift gears, and accelerate. There are some really great ways you can improve that behavior.
In this chapter, we’re assuming that as you try out the various driving activities available to MINI Cooper enthusiasts—touring and rallying, track days, or autocross—that you will start to think about making some additional improvements to your MINI Cooper. As your driving skills increase, you’ll discover some limits to the street-stock car that can easily be addressed with readily available substitute parts and accessories.
Let’s consider them in the order that we think makes sense. As you take a more active interest in your driving, and become more conscious of the car’s behavior, you’ll be ready to appreciate more responsiveness. Responsiveness is found in the feeling when you step on the brakes, shift gears, and accelerate. There are some really great ways you can improve that behavior.
Saturday, February 21, 2009
Casual Autocrossing the MINI Cooper
Autocrossing has been a popular competitive sports car activity since the earliest days of sports car driving in the United States. Offering a competitive atmosphere and the opportunity to challenge your own driving ability and the car’s capabilities, these events provide adrenalin-boosting excitement and the chance to improve your driving skills under very safe conditions.
An autocross is a race against the clock over a course laid out in a large open, paved area, such as a stadium parking lot, or occasionally on an auto racing track. The course is marked out by plastic traffic cones, and typically will include one or two longer straightaways, often ending in abrupt turns, tight and loose curves, and at least one section that requires the driver to weave in and out of a straight line of cones. Because the cones are plastic, if the driver strays off course, no damage will be done to anything except the driver’s score and ego.
Typically at an autocross, all participants will have the opportunity first to walk through the course to figure out how best to navigate the turns and curves in the most rapid means possible. Then, running one at a time, each participant will have two or three opportunities to drive the course. Times are generally taken to a tenth or hundredth of a second by automatic timing devices. A typical run will last from 30 seconds to two minutes, depending on the length and complexity of the course that has been laid out. Time will be added to the recorded time for each cone that is displaced during the run.
Even though the courses are quite short, limited by the confines of the size of the parking lot where the course is laid out, and top speeds don’t often exceed 40 miles per hour, autocrossing is an excellent way to learn to drive better. Since the basic skills or driving consist of controlling a car while accelerating, braking, and turning, and an autocross consists of nothing except accelerating, braking, and turning, every second on the course helps improve driving skills. There is a hard-core group of competitors participating in these autocross competitions, but the majority of participants simply want to enjoy the fun of revving engines and squealing tires.
For these hobbyists the opportunity to learn to drive better, have some fun with other car nuts, and enjoy a pleasant day outside is sufficient reason to participate. Since the organizations that sponsor these events thrive on attendance every effort is made to make the first-time novice feel welcome, get adapted to the procedures, and learn how to drive their car better in this exciting activity.The costs of autocross participation generally are quite low, often less than $25 for a full day’s events. Safety requirements are similar to track day events, with each car passing a tech inspection before running, focusing on wheels, tires, steering, suspension, and brakes. For most events a safety helmet rated for automobile or motorcycle use is required.
A number of local sports car clubs sponsor autocross events, but the major organizer of these events is the Sports Car Club of America (SCCA). The SCCA is divided into individual regions and districts, so it’s likely that there is a local SCCA organization near you that organizes autocross events. Check the national SCCA website (www.scca.com) to find a local club near you, then look at their web site for information on activities and schedules. Find out when the next autocross is taking place in your area, and drive out to see what it’s all about. An excellent website for the novice and experienced autocrosser, You’ll probably find at least one new MINI, and probably more, already actively involved in SCCA autocrossing, and the owner will be happy to tell you why he or she likes autocrossing and how to get involved yourself.
An autocross school is another way to sample the fun of autocrossing while improving your driving skills. Many of the regional SCCA clubs have organized autocross schools, and at least one commercial group—Evolution Performance Driving School—offers an excellent one-day school in conjunction with local clubs (www.autocross.com/evolution). As with the road-racing courses, we strongly recommend these schools whether you just want to learn a little more driving you MINI, or are thinking about becoming a serious autocrosser. The nice thing about organized autocrossing is that cars are classed by their level of preparation, so you don’t have to worry about competing directly against extensively-modified cars with your totally showroom-level MINI. In fact, SCCA currently offers four classes for street-legal cars, in addition to three classes for race-prepared cars. The “Stock” class is for cars that are equipped exactly as they came from the dealer (with a few exceptions such as allowing any tires and wheels of the same size as original equipment).
For owners who wish to upgrade the performance of their MINIS, the “street-touring,” “street-prepared,” and “street-modified” classes permit nearly all the modifications discussed in the first three sections of this book at increasing levels of modification. You can check the SCCA regulations for exact information, and if you get serious about autocrossing, more experienced participants will be happy to explain the differences among the classes.If you want to learn more about autocrossing, there is a variety of good information on autocrossing on the web for both novices and experienced drivers. A good place to start is www.autocross.com which includes both excellent information and great links to other websites on related topics..
An autocross is a race against the clock over a course laid out in a large open, paved area, such as a stadium parking lot, or occasionally on an auto racing track. The course is marked out by plastic traffic cones, and typically will include one or two longer straightaways, often ending in abrupt turns, tight and loose curves, and at least one section that requires the driver to weave in and out of a straight line of cones. Because the cones are plastic, if the driver strays off course, no damage will be done to anything except the driver’s score and ego.
Typically at an autocross, all participants will have the opportunity first to walk through the course to figure out how best to navigate the turns and curves in the most rapid means possible. Then, running one at a time, each participant will have two or three opportunities to drive the course. Times are generally taken to a tenth or hundredth of a second by automatic timing devices. A typical run will last from 30 seconds to two minutes, depending on the length and complexity of the course that has been laid out. Time will be added to the recorded time for each cone that is displaced during the run.
Even though the courses are quite short, limited by the confines of the size of the parking lot where the course is laid out, and top speeds don’t often exceed 40 miles per hour, autocrossing is an excellent way to learn to drive better. Since the basic skills or driving consist of controlling a car while accelerating, braking, and turning, and an autocross consists of nothing except accelerating, braking, and turning, every second on the course helps improve driving skills. There is a hard-core group of competitors participating in these autocross competitions, but the majority of participants simply want to enjoy the fun of revving engines and squealing tires.
For these hobbyists the opportunity to learn to drive better, have some fun with other car nuts, and enjoy a pleasant day outside is sufficient reason to participate. Since the organizations that sponsor these events thrive on attendance every effort is made to make the first-time novice feel welcome, get adapted to the procedures, and learn how to drive their car better in this exciting activity.The costs of autocross participation generally are quite low, often less than $25 for a full day’s events. Safety requirements are similar to track day events, with each car passing a tech inspection before running, focusing on wheels, tires, steering, suspension, and brakes. For most events a safety helmet rated for automobile or motorcycle use is required.
A number of local sports car clubs sponsor autocross events, but the major organizer of these events is the Sports Car Club of America (SCCA). The SCCA is divided into individual regions and districts, so it’s likely that there is a local SCCA organization near you that organizes autocross events. Check the national SCCA website (www.scca.com) to find a local club near you, then look at their web site for information on activities and schedules. Find out when the next autocross is taking place in your area, and drive out to see what it’s all about. An excellent website for the novice and experienced autocrosser, You’ll probably find at least one new MINI, and probably more, already actively involved in SCCA autocrossing, and the owner will be happy to tell you why he or she likes autocrossing and how to get involved yourself.
An autocross school is another way to sample the fun of autocrossing while improving your driving skills. Many of the regional SCCA clubs have organized autocross schools, and at least one commercial group—Evolution Performance Driving School—offers an excellent one-day school in conjunction with local clubs (www.autocross.com/evolution). As with the road-racing courses, we strongly recommend these schools whether you just want to learn a little more driving you MINI, or are thinking about becoming a serious autocrosser. The nice thing about organized autocrossing is that cars are classed by their level of preparation, so you don’t have to worry about competing directly against extensively-modified cars with your totally showroom-level MINI. In fact, SCCA currently offers four classes for street-legal cars, in addition to three classes for race-prepared cars. The “Stock” class is for cars that are equipped exactly as they came from the dealer (with a few exceptions such as allowing any tires and wheels of the same size as original equipment).
For owners who wish to upgrade the performance of their MINIS, the “street-touring,” “street-prepared,” and “street-modified” classes permit nearly all the modifications discussed in the first three sections of this book at increasing levels of modification. You can check the SCCA regulations for exact information, and if you get serious about autocrossing, more experienced participants will be happy to explain the differences among the classes.If you want to learn more about autocrossing, there is a variety of good information on autocrossing on the web for both novices and experienced drivers. A good place to start is www.autocross.com which includes both excellent information and great links to other websites on related topics..
Friday, January 23, 2009
MINI Cooper Club Track Days
Perhaps leafy byways aren’t your cup of tea, or you just want to really feel what it’s like to run your car to its rev limits in fourth gear without watching in the rear view mirror for flashing lights on a black-and-white. In that case, you might want to consider taking the car out on an automobile race tracks near you for a track day.
These events are held at nearly every race track in the country, sponsored by local automobile clubs, commercial groups or, occasionally, local MINI Cooper dealerships. Generally held on weekdays or off-weekends, they offer a chance to take your MINI Cooper out on a real track for some serious practice.
Track days are somewhere between formal driving schools and actual auto racing events. On the one hand, instruction is available, but optional and you have the opportunity to take things at your own speed. On the other hand, nobody is going to be waving a green flag except to tell you that the track is open, or a checker flag except to tell you that your session is over.
At these events, competitive racing is discouraged and aggressive driving can even be reason to ask a driver to leave. In fact, passing is generally only allowed on specific portions of the track and then only so that slower drivers won’t be hounded by faster drivers on their bumpers. But you do have the opportunity to really wind the car well beyond public road speed limits, and take it through the corner fast with no fear that anyone is going to be coming the other way.
At most track days, drivers are divided into individual groups by level of skill and experience. For example, one group will consist of drivers who have never been on a track before, one group will be for drivers who have some experience but don’t want to drive at very high speeds, and one group for drivers who have significant experience and want to practice racing and car control techniques. During the day, these three groups will alternate, typically with each on the track for 20 minutes of every hour, with the remaining time spent checking their cars or sharing information and experiences in a classroom setting.
At many of these events, very experienced drivers will be available as coaches, especially for the novice group, to ride along and offer advice on how the driver can improve his or her driving technique. Typically, novices will spend the first few sessions learning the safe “line” around the track and will be accompanied by an instructor until they are comfortable with the track, their car, and their driving ability and are ready to solo.
Though these events are certainly fun and exciting, they have a very practical side. Track days are the best possible opportunity for individual drivers to gain more experience with their cars and develop their own driving and car control capability in a safe and legal setting.
There will be a participation fee, since the club or organization has to pay for the use of the track, as well as for the cost of staffing the track with corner workers and having a safety truck with trained safety personnel and ambulance staffed with paramedics on hand, and for the insurance required by the track. Typically these fees range from $150 for a subsidized event up to $500 for a full club day with catered lunch and professional instructors.
The few other requirements, intended primarily for the safety of all participants, are quite simple. Cars must pass a basic technical inspection, focusing on the condition of the tires, the reliability of the suspension, and the capabilities of the car’s steering and brakes.
Cars must be equipped with standard seat belts, which must be used, and the participant typically must wear a helmet that meets current auto or motorcycle safe standards. Organizers also require that all loose objects be removed from the car to prevent injury. That’s all. Aside from the helmet, the car simply has to be as safe and well-maintained as you would want it to be for highway driving.
Finding these track days isn’t too difficult. The race track websites will have schedules of all their events, with links to the organizations that are renting the track for specific events. Local sports car clubs, such as the Lotus, BMW, and Porsche clubs, sponsor track days in many parts of the country and are happy to have other enthusiasts share the costs of the event. And since the first MINI Cooper track day was sponsored at Thunderhill Racetrack in northern California by MINI of Mountain View, other MINI Cooper dealers are starting to organize their own events around the country.
These events are held at nearly every race track in the country, sponsored by local automobile clubs, commercial groups or, occasionally, local MINI Cooper dealerships. Generally held on weekdays or off-weekends, they offer a chance to take your MINI Cooper out on a real track for some serious practice.
Track days are somewhere between formal driving schools and actual auto racing events. On the one hand, instruction is available, but optional and you have the opportunity to take things at your own speed. On the other hand, nobody is going to be waving a green flag except to tell you that the track is open, or a checker flag except to tell you that your session is over.
At these events, competitive racing is discouraged and aggressive driving can even be reason to ask a driver to leave. In fact, passing is generally only allowed on specific portions of the track and then only so that slower drivers won’t be hounded by faster drivers on their bumpers. But you do have the opportunity to really wind the car well beyond public road speed limits, and take it through the corner fast with no fear that anyone is going to be coming the other way.
At most track days, drivers are divided into individual groups by level of skill and experience. For example, one group will consist of drivers who have never been on a track before, one group will be for drivers who have some experience but don’t want to drive at very high speeds, and one group for drivers who have significant experience and want to practice racing and car control techniques. During the day, these three groups will alternate, typically with each on the track for 20 minutes of every hour, with the remaining time spent checking their cars or sharing information and experiences in a classroom setting.
At many of these events, very experienced drivers will be available as coaches, especially for the novice group, to ride along and offer advice on how the driver can improve his or her driving technique. Typically, novices will spend the first few sessions learning the safe “line” around the track and will be accompanied by an instructor until they are comfortable with the track, their car, and their driving ability and are ready to solo.
Though these events are certainly fun and exciting, they have a very practical side. Track days are the best possible opportunity for individual drivers to gain more experience with their cars and develop their own driving and car control capability in a safe and legal setting.
There will be a participation fee, since the club or organization has to pay for the use of the track, as well as for the cost of staffing the track with corner workers and having a safety truck with trained safety personnel and ambulance staffed with paramedics on hand, and for the insurance required by the track. Typically these fees range from $150 for a subsidized event up to $500 for a full club day with catered lunch and professional instructors.
The few other requirements, intended primarily for the safety of all participants, are quite simple. Cars must pass a basic technical inspection, focusing on the condition of the tires, the reliability of the suspension, and the capabilities of the car’s steering and brakes.
Cars must be equipped with standard seat belts, which must be used, and the participant typically must wear a helmet that meets current auto or motorcycle safe standards. Organizers also require that all loose objects be removed from the car to prevent injury. That’s all. Aside from the helmet, the car simply has to be as safe and well-maintained as you would want it to be for highway driving.
Finding these track days isn’t too difficult. The race track websites will have schedules of all their events, with links to the organizations that are renting the track for specific events. Local sports car clubs, such as the Lotus, BMW, and Porsche clubs, sponsor track days in many parts of the country and are happy to have other enthusiasts share the costs of the event. And since the first MINI Cooper track day was sponsored at Thunderhill Racetrack in northern California by MINI of Mountain View, other MINI Cooper dealers are starting to organize their own events around the country.
Sunday, January 18, 2009
Serious MINI Coopers for Touring, Track and Autocross
If you’re working your way through this book one step at a time, by now you have gotten a few weeks or months experience with your MINI Cooper. We also hope you have taken the opportunity to participate in a basic one-day driving school where you got more comfortable with the car’s handling and performance, and learned some safe-driving techniques. If not, we hope you’ve at least used that anti-lock braking system, tried a few quick lane changes, and squealed the tires a little on a back road or empty parking lot.
Perhaps you’ve also upgraded the basic engine performance and bought those aftermarket wheels and tires that give the car a distinctive appearance and improve its handling. But there is still more to be done and more to experience. In this chapter we’ll discuss several ways that you can get a little more excitement out of your motoring experience. We’ll offer some ideas for further performance upgrades to suit the driving you’re starting to do. Finally, we’ll give you some tips on high-performance driving to take advantage of the capabilities of your MINI Cooper.
What Can We Do Next?
In your everyday driving, by now you’ve discovered how much fun your MINI Cooper can provide, especially when you can let it out a little bit and experienced its estimable performance and handling capabilities. But if you really want to have some fun with that great MINI Cooper, we encourage you to try some of the various kinds of organized events that are available to you. You can head out on the highway for club tours, participate in organized track days, or try your mettle against the clock in autocross events.
Backroads Touring in a MINI Cooper
In every part of the country, there are interesting roads that allow you to get off the interstate and enjoy the sights and sounds of nature and geography. When you do that, you begin to experience the automobile not just as a way to get from one place to another, but rather as a source of enjoyment in itself. And you discover how much fun driving can be, even within the prescribed speed limits of public roads.
You can explore other times by visiting historical sights, you can expand your senses by getting closer to scenic wonders, or you might just pack a picnic lunch and find a place off the beaten path where you can relax for a few hours away from the noise and confusion of the city. Or you can just spend a day or two becoming one with the spirited handling and performance of your car on some curving backroads through hills and valleys, with no other purpose in mind but to enjoy the drive.
While you can do any of these on your own, simply by getting out your map and guidebook and doing some internet exploring to find places to visit and stay, the trips will be much more fun if there is a MINI Cooper in front of you, and another in your rearview mirror. In other words, take a tour with a local MINI Cooper club or some MINI Cooper friends.
In some parts of the country, competitive time-speed-distance rallies are still sponsored by local sports car clubs. These TSD rallies have a competitive element that often appeals to car enthusiasts, but under controlled legal circumstances. Essentially, a TSD rally measures your ability to drive a route that has been laid out by the “rallymaster” with your results determined by how close you can match the exact speeds driven by the rallymaster over the route.
Directions are spelled out in a shorthand that is defined in the rally’s general instructions—“R at 1st op,” for example means turn right at the first opportunity after executing the previous instruction—and exact speeds are specified for each leg of the rally, always at levels that can be achieved without exceeding speed limits. By driving each leg at the specified speed—say, 36 mph—and carefully following the instructions, you try to arrive at each checkpoint at an exact time. Points are deducted for each second you arrive early or late to the check point.
These TSD rallies challenge the ability of the driver and navigator to carefully follow the instructions and maintain the specified speeds, which requires a significant amount of driving discipline. The rewards are the opportunities to drive through interesting countryside, and share experiences with other individuals who are trying to meet the same challenges.
The best way to get involved in activities like these is through a local MINI Cooper club, if one already exists in your area. If one doesn’t exist, your local dealer may be willing to help you organize one, or at least introduce you to some other new MINI Coper owners with whom you can do some driving events.
If there aren’t yet enough MINI Coopers in your area to have your own single-marque club, you might instead see if there is a local British car club or more general sports car club in your region. Regardless, it shouldn’t take long to find a group of like-minded enthusiasts who enjoy driving their cars and organize events for just that purpose.
All that is required to enjoy one of these events is a willing interest to participate and a safe, reliable car that is fun to drive. You supply the first and your MINI Cooper will happily fill the bill for the second. Nevertheless, the better your car’s performance and handling, the more pleasure you’re likely to get out of the experience.
Perhaps you’ve also upgraded the basic engine performance and bought those aftermarket wheels and tires that give the car a distinctive appearance and improve its handling. But there is still more to be done and more to experience. In this chapter we’ll discuss several ways that you can get a little more excitement out of your motoring experience. We’ll offer some ideas for further performance upgrades to suit the driving you’re starting to do. Finally, we’ll give you some tips on high-performance driving to take advantage of the capabilities of your MINI Cooper.
What Can We Do Next?
In your everyday driving, by now you’ve discovered how much fun your MINI Cooper can provide, especially when you can let it out a little bit and experienced its estimable performance and handling capabilities. But if you really want to have some fun with that great MINI Cooper, we encourage you to try some of the various kinds of organized events that are available to you. You can head out on the highway for club tours, participate in organized track days, or try your mettle against the clock in autocross events.
Backroads Touring in a MINI Cooper
In every part of the country, there are interesting roads that allow you to get off the interstate and enjoy the sights and sounds of nature and geography. When you do that, you begin to experience the automobile not just as a way to get from one place to another, but rather as a source of enjoyment in itself. And you discover how much fun driving can be, even within the prescribed speed limits of public roads.
You can explore other times by visiting historical sights, you can expand your senses by getting closer to scenic wonders, or you might just pack a picnic lunch and find a place off the beaten path where you can relax for a few hours away from the noise and confusion of the city. Or you can just spend a day or two becoming one with the spirited handling and performance of your car on some curving backroads through hills and valleys, with no other purpose in mind but to enjoy the drive.
While you can do any of these on your own, simply by getting out your map and guidebook and doing some internet exploring to find places to visit and stay, the trips will be much more fun if there is a MINI Cooper in front of you, and another in your rearview mirror. In other words, take a tour with a local MINI Cooper club or some MINI Cooper friends.
In some parts of the country, competitive time-speed-distance rallies are still sponsored by local sports car clubs. These TSD rallies have a competitive element that often appeals to car enthusiasts, but under controlled legal circumstances. Essentially, a TSD rally measures your ability to drive a route that has been laid out by the “rallymaster” with your results determined by how close you can match the exact speeds driven by the rallymaster over the route.
Directions are spelled out in a shorthand that is defined in the rally’s general instructions—“R at 1st op,” for example means turn right at the first opportunity after executing the previous instruction—and exact speeds are specified for each leg of the rally, always at levels that can be achieved without exceeding speed limits. By driving each leg at the specified speed—say, 36 mph—and carefully following the instructions, you try to arrive at each checkpoint at an exact time. Points are deducted for each second you arrive early or late to the check point.
These TSD rallies challenge the ability of the driver and navigator to carefully follow the instructions and maintain the specified speeds, which requires a significant amount of driving discipline. The rewards are the opportunities to drive through interesting countryside, and share experiences with other individuals who are trying to meet the same challenges.
The best way to get involved in activities like these is through a local MINI Cooper club, if one already exists in your area. If one doesn’t exist, your local dealer may be willing to help you organize one, or at least introduce you to some other new MINI Coper owners with whom you can do some driving events.
If there aren’t yet enough MINI Coopers in your area to have your own single-marque club, you might instead see if there is a local British car club or more general sports car club in your region. Regardless, it shouldn’t take long to find a group of like-minded enthusiasts who enjoy driving their cars and organize events for just that purpose.
All that is required to enjoy one of these events is a willing interest to participate and a safe, reliable car that is fun to drive. You supply the first and your MINI Cooper will happily fill the bill for the second. Nevertheless, the better your car’s performance and handling, the more pleasure you’re likely to get out of the experience.
Saturday, January 10, 2009
Motoring On in a MINI Cooper S
Consider the upgrades we’ve suggested as means to improve the performance of your MINI Cooper, but whether or not you decide to make changes in the car right now, don’t wait to start working on your driving. Use a good driving position, practice smoothness in your starts, stops and turns, and try to find a good line around every corner. And take the next possible opportunity to take an advanced driving course so you can learn and practice the skills that will allow you to drive your MINI Cooper in the way it was intended.
After your driving school experience and with a few miles under your tires, you may find that you want to get even more out of your MINI Cooper. In the next section, we’ll discuss additional improvements that will prove their worth on the roadtrack or autocross course, and we’ll present some more advanced driving skills you’ll want to master to take advantage of those improvements.
After your driving school experience and with a few miles under your tires, you may find that you want to get even more out of your MINI Cooper. In the next section, we’ll discuss additional improvements that will prove their worth on the roadtrack or autocross course, and we’ll present some more advanced driving skills you’ll want to master to take advantage of those improvements.
Thursday, January 8, 2009
The Cornering Line in a MINI Cooper
In preparation for your MINI Cooper first driving class, and as something else to begin practicing, let’s talk about the safest and most efficient way to get around the corner. The choice of turn-in, apex, and exit points, and the pathway between them is what racers refer to as the “line” around the corner.
The optimal line around an individual corner is the one that allows you to wait as long as possible before braking, while still having enough time to bring the car down to a speed that will allow you to take the car around the corner without spinning out or sliding off the track. More important, the optimal line is the one that allows you to be going as rapidly as possible at the point when you exit the corner.
It’s an old saying around race tracks that all racing is simply a succession of drag races from corner to corner. Picking the correct line around the corner is not necessarily a matter of getting around each corner as fast as possible in your MINI Cooper. Instead, it is a matter of setting the MINI Cooper up so that you can win the drag race to the next corner.
Where you exit, and how fast you exit, depends entirely on where you start to make the turn. Selecting the turn-in point is critical to getting the corner right. After that, everything else is just follow-through.
We can start by thinking about the most basic corner, a 90-degree turn. This is a good place to start since most of our everyday driving is going to involve making right-angle turns on city streets, so there will be lots of opportunities to practice the technique.
And remember, you don’t have to be going fast in order to practice and get the moves down. In fact, for the first 100 or so times you turn the corner, you’ll have trouble remembering everything in the right order, even at normal street speeds. But practice the technique and when you do get on the track, you’ll be amazed at how soon you’ll feel comfortable on higher-speed corners, while your less-practiced friends are still looking confused as they lurch around the corner.
The first step in taking a corner is to move as wide as possible to the “outside” of the corner (the side opposite to the direction you’re turning). On the street or highway, this will usually be the center line or curb. (Of course, on deserted roads with no obstructions, where you can see all the way around the corner and up the road a good distance you might be able to go wider.) Once you’re on the track, you’ll be moving clear to the edge of the track before beginning your turn.
You’ll drive at the edge, while completing your heavy braking (and your downshifting, if the corner requires it), until you can see around the corner. While this isn’t necessarily the smoothest arc around the corner, it will be the most efficient line around the corner in terms of exit speed. It is also the safest, since you will be able to see any obstructions in your path.
At that point, you’ll begin to turn in (which, as we noted above, is called the turn-in point) and start to release your brakes. You will want to aim for the inside edge of the corner—remember, earlier we called that the “apex” of the corner—while looking for the point where you will be completing your turn and will once again be at the outside edge of your lane, or the road, the “exit point” or “track-out point.” Remember that you’re looking at where you want the car to go, not just where it is aimed at the moment.
As you reach the apex of the corner you should be off the brakes completely and already starting to ease onto the throttle. As soon as you begin straightening the wheel, you’ll roll onto the throttle and start to accelerate.
You can see from the diagram that the arc of your curve is tightest just past the turn-in point, and widest as you come out of the turn. This will allow you to get on the throttle as hard as conditions permit as early as possible and start that drag race to the next turn-in point.
The optimal line through a single corner is going to start and end at the far outside limits of the available track or lane. As you progress in racing, you’ll often be reminded to “use all the track.” What the instructor means is that if you didn’t start and end the curve at the far outside, while nearly touching the inside limit—curb, berm, or edge of the pavement—at the apex point, you will have made too tight a turn and sacrificed some of that precious speed you need.
Also notice that on this line, the apex—the point at which you touch the inside limit—is just a little way around the corner, rather than being at the actual geometric point of the corner. That “late apex” is usually the best line, since you have a good sight-line down the road when you start your turn, and that same long straight line along which to accelerate as you complete the turn.
You might think about what happens if you get a little tense and try to “hurry” the corner. You’ll start to turn in sooner than the person who’s following the line we’ve just described, but at best you won’t be able to get on the throttle until later in the turn than the other driver. At worst, you will find yourself, as racers say, “running out of road” before you’ve completed your turn, and risk running off the track.
Now all of that is a lot to practice all at once, which is why we recommend that you start now, rather than waiting until you get into the driving course. Incidentally, during the driving course, the instructor will most likely mark off the course with pylons or markers to show you the turn-in point, the apex, and the exit, which will make it a little easier. But daily driving is like rally driving; no one has put pylons out to show you the correct line, so get used to finding it on every corner on your own.
he entrance and exit ramps on limited-access highways make especially good practice areas, since you aren’t likely to encounter anyone going the other way, and the range of speed is as wide as you’ll encounter on most corners of most race tracks.
The best place to practice is on a corner you take every day. That way you can start at a fairly slow speed, and gradually speed up as you get used to the corner, changing the point where you start and end your braking, turn in for the corner, apex it, and come out at the exit point.
If you find that you are having difficulty getting around the corner, it means either that you’re going in too fast, or you’re turning too early. If that’s the case, trying slowing down a little, which will allow you to turn more tightly at the beginning, and turn in later, which will give you more room to finish the corner at the end.
As racing drivers learn new tracks, this is exactly what they are doing; searching for the optimal points and speeds to start and end each phase of each corner, then memorizing those points so they can repeat them lap after lap during an actual race.
When taking the corners, keep thinking about weight transfer as you brake, turn, and accelerate, feeling the car’s weight shift from back to front and corner to corner through the process. Downhill skiers and horseback riders often find that this process is very familiar, it’s just that there is a lot more of you to think about as the car increases and extends your mass.
As you round every corner on your way to work or wherever, make your braking, turning, and accelerating as smooth as possible and try to pick a good line around each one of those corners. If you do your practice diligently every chance you get, pretty soon you’ll start to feel at one with the car, anticipating the weight transfers and feeling yourself going with them, with no abrupt transitions and with as much speed as the situation allows. In short, you’ll really be motoring.
The optimal line around an individual corner is the one that allows you to wait as long as possible before braking, while still having enough time to bring the car down to a speed that will allow you to take the car around the corner without spinning out or sliding off the track. More important, the optimal line is the one that allows you to be going as rapidly as possible at the point when you exit the corner.
It’s an old saying around race tracks that all racing is simply a succession of drag races from corner to corner. Picking the correct line around the corner is not necessarily a matter of getting around each corner as fast as possible in your MINI Cooper. Instead, it is a matter of setting the MINI Cooper up so that you can win the drag race to the next corner.
Where you exit, and how fast you exit, depends entirely on where you start to make the turn. Selecting the turn-in point is critical to getting the corner right. After that, everything else is just follow-through.
We can start by thinking about the most basic corner, a 90-degree turn. This is a good place to start since most of our everyday driving is going to involve making right-angle turns on city streets, so there will be lots of opportunities to practice the technique.
And remember, you don’t have to be going fast in order to practice and get the moves down. In fact, for the first 100 or so times you turn the corner, you’ll have trouble remembering everything in the right order, even at normal street speeds. But practice the technique and when you do get on the track, you’ll be amazed at how soon you’ll feel comfortable on higher-speed corners, while your less-practiced friends are still looking confused as they lurch around the corner.
The first step in taking a corner is to move as wide as possible to the “outside” of the corner (the side opposite to the direction you’re turning). On the street or highway, this will usually be the center line or curb. (Of course, on deserted roads with no obstructions, where you can see all the way around the corner and up the road a good distance you might be able to go wider.) Once you’re on the track, you’ll be moving clear to the edge of the track before beginning your turn.
You’ll drive at the edge, while completing your heavy braking (and your downshifting, if the corner requires it), until you can see around the corner. While this isn’t necessarily the smoothest arc around the corner, it will be the most efficient line around the corner in terms of exit speed. It is also the safest, since you will be able to see any obstructions in your path.
At that point, you’ll begin to turn in (which, as we noted above, is called the turn-in point) and start to release your brakes. You will want to aim for the inside edge of the corner—remember, earlier we called that the “apex” of the corner—while looking for the point where you will be completing your turn and will once again be at the outside edge of your lane, or the road, the “exit point” or “track-out point.” Remember that you’re looking at where you want the car to go, not just where it is aimed at the moment.
As you reach the apex of the corner you should be off the brakes completely and already starting to ease onto the throttle. As soon as you begin straightening the wheel, you’ll roll onto the throttle and start to accelerate.
You can see from the diagram that the arc of your curve is tightest just past the turn-in point, and widest as you come out of the turn. This will allow you to get on the throttle as hard as conditions permit as early as possible and start that drag race to the next turn-in point.
The optimal line through a single corner is going to start and end at the far outside limits of the available track or lane. As you progress in racing, you’ll often be reminded to “use all the track.” What the instructor means is that if you didn’t start and end the curve at the far outside, while nearly touching the inside limit—curb, berm, or edge of the pavement—at the apex point, you will have made too tight a turn and sacrificed some of that precious speed you need.
Also notice that on this line, the apex—the point at which you touch the inside limit—is just a little way around the corner, rather than being at the actual geometric point of the corner. That “late apex” is usually the best line, since you have a good sight-line down the road when you start your turn, and that same long straight line along which to accelerate as you complete the turn.
You might think about what happens if you get a little tense and try to “hurry” the corner. You’ll start to turn in sooner than the person who’s following the line we’ve just described, but at best you won’t be able to get on the throttle until later in the turn than the other driver. At worst, you will find yourself, as racers say, “running out of road” before you’ve completed your turn, and risk running off the track.
Now all of that is a lot to practice all at once, which is why we recommend that you start now, rather than waiting until you get into the driving course. Incidentally, during the driving course, the instructor will most likely mark off the course with pylons or markers to show you the turn-in point, the apex, and the exit, which will make it a little easier. But daily driving is like rally driving; no one has put pylons out to show you the correct line, so get used to finding it on every corner on your own.
he entrance and exit ramps on limited-access highways make especially good practice areas, since you aren’t likely to encounter anyone going the other way, and the range of speed is as wide as you’ll encounter on most corners of most race tracks.
The best place to practice is on a corner you take every day. That way you can start at a fairly slow speed, and gradually speed up as you get used to the corner, changing the point where you start and end your braking, turn in for the corner, apex it, and come out at the exit point.
If you find that you are having difficulty getting around the corner, it means either that you’re going in too fast, or you’re turning too early. If that’s the case, trying slowing down a little, which will allow you to turn more tightly at the beginning, and turn in later, which will give you more room to finish the corner at the end.
As racing drivers learn new tracks, this is exactly what they are doing; searching for the optimal points and speeds to start and end each phase of each corner, then memorizing those points so they can repeat them lap after lap during an actual race.
When taking the corners, keep thinking about weight transfer as you brake, turn, and accelerate, feeling the car’s weight shift from back to front and corner to corner through the process. Downhill skiers and horseback riders often find that this process is very familiar, it’s just that there is a lot more of you to think about as the car increases and extends your mass.
As you round every corner on your way to work or wherever, make your braking, turning, and accelerating as smooth as possible and try to pick a good line around each one of those corners. If you do your practice diligently every chance you get, pretty soon you’ll start to feel at one with the car, anticipating the weight transfers and feeling yourself going with them, with no abrupt transitions and with as much speed as the situation allows. In short, you’ll really be motoring.
Monday, January 5, 2009
Heel and Toe Downshifting in a MINI Cooper
In normal driving, very few people downshift, since the MINI Cooper engine can pull pretty strongly from very low rpm and there are few times when the additional torque is really necessary. But if you want to practice for the day you start doing hot laps at the race track, you can start working on how to downshift, using the technique called “heel-and-toe” shifting to make those shifts as smooth as possible.
Essentially, what you are going to do is make it easier for the engine to cope with the changes in gears by giving the throttle a little blip while you’re downshifting. That way, before the shift is completed, the engine is already spinning close to the higher rpm required in the lower gear. Done properly, this little blip of the throttle will make your driving much smoother, and eventually much faster.
What makes this process a little complicated is that you are going to start downshifting at the same time that you are braking to get ready for the corner. At the same time that you’re putting on the brake with your right foot, you’re going to want to tap the gas pedal with your right foot. “But wait a minute,” you say. “I only have one right foot.”
Right you are. So what you will do is to push the brake in with the toe of your right foot, and by twisting your foot slightly, give the throttle a nudge with your right heel. If it’s more comfortable for you, you can push the brake with your heel and the throttle with your toe. That’s why the technique is called heel-and-toe. (Though to be honest, some people use one side of the foot on the brake and the other side of the foot on the gas. Whatever works for you.)
So here’s the sequence: As you get ready to turn a corner that is going to require that you exit in a lower gear than you entered, you will start to brake with your right foot and at the same time push in the clutch with your left. With the clutch in, you’ll slide the gear shift into the next lower gear and about the same time blip the throttle. With the engine still revving up from the throttle blip, you’ll let out the clutch. Brake, push clutch, shift/blip, release clutch.
Right now this may seem a little like patting your head while rubbing your stomach, but a little practice will make it all work. Incidentally, if anyone asks, you are not “double-clutching.” Double-clutching is actually a more complicated process that requires releasing the clutch slightly at the point that the throttle is blipped in order to get the gears spinning faster, then pushing it back in to shift the gear, before releasing the clutch. Thankfully, with modern engines and gear boxes, the technique is no longer required, except on some really, really old vintage cars.
Of course, if you remember the original cornering sequence we just discussed, we didn’t discuss shifting gears. That does add one additional step to the sequence. However, the downshifting should be completed during the early part of the braking process, while the car is still going in a straight line. By the time you start to make the turn, you want all your shifting done, so you can have both hands on the wheel through the corner.
Essentially, what you are going to do is make it easier for the engine to cope with the changes in gears by giving the throttle a little blip while you’re downshifting. That way, before the shift is completed, the engine is already spinning close to the higher rpm required in the lower gear. Done properly, this little blip of the throttle will make your driving much smoother, and eventually much faster.
What makes this process a little complicated is that you are going to start downshifting at the same time that you are braking to get ready for the corner. At the same time that you’re putting on the brake with your right foot, you’re going to want to tap the gas pedal with your right foot. “But wait a minute,” you say. “I only have one right foot.”
Right you are. So what you will do is to push the brake in with the toe of your right foot, and by twisting your foot slightly, give the throttle a nudge with your right heel. If it’s more comfortable for you, you can push the brake with your heel and the throttle with your toe. That’s why the technique is called heel-and-toe. (Though to be honest, some people use one side of the foot on the brake and the other side of the foot on the gas. Whatever works for you.)
So here’s the sequence: As you get ready to turn a corner that is going to require that you exit in a lower gear than you entered, you will start to brake with your right foot and at the same time push in the clutch with your left. With the clutch in, you’ll slide the gear shift into the next lower gear and about the same time blip the throttle. With the engine still revving up from the throttle blip, you’ll let out the clutch. Brake, push clutch, shift/blip, release clutch.
Right now this may seem a little like patting your head while rubbing your stomach, but a little practice will make it all work. Incidentally, if anyone asks, you are not “double-clutching.” Double-clutching is actually a more complicated process that requires releasing the clutch slightly at the point that the throttle is blipped in order to get the gears spinning faster, then pushing it back in to shift the gear, before releasing the clutch. Thankfully, with modern engines and gear boxes, the technique is no longer required, except on some really, really old vintage cars.
Of course, if you remember the original cornering sequence we just discussed, we didn’t discuss shifting gears. That does add one additional step to the sequence. However, the downshifting should be completed during the early part of the braking process, while the car is still going in a straight line. By the time you start to make the turn, you want all your shifting done, so you can have both hands on the wheel through the corner.
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