I went to the track this Sunday and at around 80 mph I have to turn the steering wheel 45* to the right to keep my car going straight. It wants to pull hard to the left.

Today I took the car up to 140 mph with street tires and it goes perfectly straight. Something's up with these M&H slicks. They are 24.5x8.5x15

I took them off and measured circumference all at 25 psi.

LF: 80" RF: 79"
LR: 79" RR: 79.5"

Which leads me it would pull right but it was pulling hard left.

My suspension is setup:

Front camber: -0.5*
Rear camber: +0.5*

Toe F&R is set to 0

 

Cross rotate the fronts and see if it goes opposite.

Also whats the caster difference?

Aaron

 

corner weight your car. (with a driver in the driver's seat)

 

I'll try to switch the fronts and see if that helps. I have no idea on the caster.

I will definitely corner weight it after I do my weight reductions this winter.

 

Yeah my thoughts too....swap the front two side to side see if it pulls to the right then.

Other than that match the axle pairs so there is little side to side diff.

With such a large diff, you will be increasing the stress on the center diff. See Neal's thread on tire matching, all four need to be similar. And rotate often :=)

 

I ran 25" MH & 24.5MT slicks on a 400wtq FWD car for probably a little over 200 passes... it would ONLY pull to one side or the other off the line if my corner weights were way off.

I made sure I had the same normal force on the front two tires, then I just had to have a reasonable alignment, the same tire pressure in each tire to go straight.