Last weekend at the local track (High Plains Raceway) I experienced something I've never experienced before. When threshold braking the steering wheel provided me with significant resistance while threshold braking. There are a couple turns at High Plains Raceway at which it was very noticeable. In turns 2 and 6 it became an increasingly annoying problem and got worse the faster I went. These are both turns that I enter going around 70 or 80 mph (sorry, no data acquisition available).
I was braking hard going into the turns and pulling noticeably harder on the steering wheel to get the car to turn in. Then, still providing similar steering angle, I release the brakes slowly and feel significantly less resistance from the steering wheel. Even though the steering angle didn't change, the attitude of the car did, and it began to rotate much better. There seems to be some kind of correlation between the two.
Additionally, the car seems to understeer when this is happening. The front end just doesn't bite like I'm used to. As soon as I release the brakes, the front end just digs in and goes right where I want it to.
Keep in mind what I'm experiencing is not simply the car pushing. The car's attitude changes as soon as I feel less resistance in the steering wheel.
My car's stats as it sits now:
stock suspension
BFG R1S at 29 psi hot
Even tire temps all around except +15 degrees F on the front tires' inner shoulders
stock brakes other than DTC 60s and Togue Factory ducts
RCE street camber plates
Stock caster, 3.2* of front camber, zero toe
I'd like to stress that the front end seems to turn in properly when the steering wheels resistance went away, not when I released the brake pedal. Although they happened pretty much at the same time, it seemed to me the car's attitude changed depending on the resistance to the steering wheel and not specifically the brake pedal. I don't know why it felt that way to me, but it did.
Who else has experienced this? Any ideas why this is happening?
For what it's worth, my best lap last weekend was a 2:10.7 on an
exceptionally slippery track. I'm guessing the best it was capable of was high 2:09s, but that would be
really pushing it in this trim. Maybe that'll give any local guys more perspective and help with diagnosis.