I thought that I would kick of the rally-cross school spirit early and offer some things to think about. I believe that there are two things to learn here: first you need to learn what you want the car to do, and the second you need to learn how to make the car do it. So: first visualize how the car should behave, and then train your reflexes to generate that behavior…
But… I don’t believe that there is a right way to rally-cross. Every car and driver is different; you have to figure out what works for you and your car.
These are a few of _my_ ideas that seem to work, but consider them only as concepts. They might not work for you… (And remember that these are based on front wheel drive experience.)
Be smooth: you have to work the gas and brake constantly, but try to make small adjustments and not surge on-off.
Hit your marks: figure out what line you want to follow, and work hard to follow it. It is almost always better to slow down a fraction early, hit your mark, and then:
Carry speed: try not to over-brake because it is often difficult to get accelerated again.
Rotate, don’t steer: In order to carry speed you have to keep the car moving the direction that you want it to go. Steering is one way to cause the car to rotate, but it is dependent on traction. You can also rotate the car with brakes, left-foot braking, or plain-old weight transfer physics. Try not to rely only on the steering wheel to rotate the car.
There is another benefit: you will generally get the best traction with the tire flat on the ground. When you turn the front wheels, you get camber change that tips the tire over. You also twist the outer CV joint, and when you are pounding up and down under max throttle, it is best to keep the CV straight as possible to protect it. So if you can keep the front wheels pointed fairly straight and rotate the car, you should get the best traction and the least stress on the car. (and probably also reduce the odds of de-beading a tire.)
Of course you still have to steer, especially at low speed. But the faster you go, the smaller the steering wheel angles ought to be.
Center of mass: keep track of where the car is actually going, not where it is pointed. This was especially true in the mud at the last rally-x. The car was often rapidly swinging through angles that didn’t feel right, but the car was still sliding in the proper direction. Don’t fret, you are still moving in the right direction, just keep working to get the nose pointed around toward the next corner. Don’t panic, and don’t nail the brakes.
Left-foot braking: left-foot braking is always controversial. It is not required, but I find it to be helpful. Left-felt braking is a great way to rotate the car because it basically allows you shift the brake bias in the car to the rear when you wish to, and therefore “slide” the rear alittle bit.
But I think that there is another reason for left-foot braking: instant torque control. The brakes can directly adjust the torque reaching the tires. The throttle pedal is an in-direct control. The throttle pedal moves the throttle plate, which alters the amount of air reaching the engine, which is measured and then used to alter the amount of fuel available, which then changes the torque at the crank and transmission, which passes through the gears and CV joints after the lash (slop) is taken up, and the entire drivetrain moves on its flexible mounts until it stabilizes at the new torque setting. This is a lot of events which have to occur before the torque at the tires actually changes. It may only take a fraction of second for all this stuff to stabilize, but there is a lag between throttle pedal movement and torque change. And when you are trying to balance the car on the hairy edge, this continual time lag doesn’t help. So you can use light application of the brakes to very quickly modulate the torque at the tires. (and keep the engine pulling happily.)
Left-foot braking is tricky, and requires lots of practice, and just flat doesn’t work for some people. But, just think about it…
Here is some additional reading for you:
http://en.wikipedia.org/wiki/Rallying#R ... techniques
Go to “Rally Driving Techniques” and read the sections for:
- Scandinavian Flick
- Left-foot braking
And then watch the compilation of old videos that Simon just posted. Watching Blomqvist in a Saab 96 can teach you everything you need to know about driving front wheel drive. And marvel at the guys driving the Lancia Stratos. Those guys had balls so big you could see them from outer space. Unbelieveable…
Ready?
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Yep, I suck.