Brake Clinic

[catchacab]

Larry Herman wrote:

Thanks Guys. We will have to figure out another topic to cover for maybe an August session. We started to get into a little suspension/shock discussion after it thinned out. That may be a good subject, or maybe a primer on wheels, offsets, tires and how it affects the cars related to DE driving. We can also cover mounting and balancing if that is not too simplistic.

In answer to George's question as to why his car wears out the rear brakes first, it's one of those head-smacking answers...the PSM! The basic control that PSM exerts over the car is to independently brake either of the 2 rear wheels to correct impending yaw. If the car is understeering it may brake the outside rear in order to get the car to "follow" the steering input. If the car is starting to oversteer, it would brake the inside rear to try and stabilze the car. If either of the rear wheels starts to lose traction under acceleration, it will apply the brake to that wheel to keep it from spinning. Little wonder why the back brakes show so much wear. Without PSM, they are usually just along for the ride.

I was just reading an article about a modified 997GT3 in the latest excellence, and the author stated that there is a rear brake bias on the cars from the factory.