Thursday, February 28, 2008

Going Fast is All About Stopping

Any racing driver will tell you that speed doesn’t matter. That’s why most real racing cars don’t even have a speedometer. We would argue that the same thing is true in everyday driving. As long as you’re not over the speed limit, you won’t get a ticket, but that’s really the only instance where it even matters what the speedometer says. What does matter is the distance the car will go in the time that it takes to notice and react appropriately to changes in conditions. Here are three rules of thumb that will tell you whether you’re going too fast. Stopping Distance
We’ve already recommended that you look a long distance down the road to anticipate what might happen before it happens, but what really matters is how long it takes for you to stop or change directions before you hit the car ahead of you. We all know that the faster we’re going, the more distance we’ll cover before we can hit the brake pedal, or turn the wheel. We also know that the faster we’re going, the longer it will take to stop, and that we shouldn’t turn the wheel abruptly at high speeds because that will cause the car to swerve.
But we can’t look up our speed and distance in car lengths in some book every time we want to know whether we’re driving too close to the car ahead, or whether the car behind us has enough room to stop if we do have to stop ourselves.
To determine how close you should be to the car ahead of you, all you need to do is count to three. Notice when the car ahead passes a particular point, such as a tree or mile marker. If you can count to three slowly before you get to that point, then you have room to bring your car to a stop, or turn into the next lane, should the car ahead stop or swerve abruptly. No matter how fast you’re going, it will take three seconds for you to get your foot from the gas to the brake, and bring the car to a stop.
What about the car behind you? When you’re passing, or changing lanes, you want enough room to give the car behind a safe space. As you pass the car ahead, wait until you can see them completely in your inside rearview mirror. If you can see them completely in your rearview mirror, it’s safe to move over into their lane. Remember that your side mirrors have been adjusted to cover your blind spots, which are close to you, and that the right mirror says “Objects in the mirror are closer than they appear.”
On the road or on the track, it isn’t enough just to be ahead of the person you’ve just passed before you change your line. You need to be far enough ahead of them to cut over into their path and still give them time to react.
But what about when you can’t see the car ahead? Curves are another place where we often drive faster than we should. After cleaning auto wreckage off curves for many years, the highway departments of America finally figured this out and started posting warning signs, with a suggested speed for that curve.
Unfortunately, most of us see these signs as challenges since we think they are the fastest speed that the highway department thinks the average driver can get their car around the curve. So we see how much faster we can go than the warning sign. “I took a curve at 40 mph that was posted at 20 mph. I guess I’m twice as good as the average driver,” we say.
Too bad that’s not what the sign means. What it means is that, if there is something in the road ahead that you can’t see, the posted speed is the fastest your car can be going and still have time to stop when you do see the obstacle. You can test the laws of physics if you like, but you won’t win.
On an open race track, things will be different. There will be a person on the corner looking around the bend for you, to wave a yellow flag if there’s a problem while you’ve still got time enough to stop. That’s the place to see just how fast you can get the car around the corner, because if the corner worker isn’t waving the flag, you can be sure there isn’t anything there. But on the highway, with no corner worker, it’s best to slow down to the recommended speed. The stalled driver, bicycle rider, or deer you have time to avoid will thank you for it.
That’s enough driving lesson for one day. But if you’ll practice a good driving position, get used to thinking 360 degrees and into the future, and not going faster than you can stop, you’ll be a better driver when your new MINI arrives at your dealer, and be ready for our next lesson in motoring.

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