So this is my brothers trans am. We put a 9” under it with a short mwc torque arm like I have on my car. Threw it in and had to do some massaging in the fender well area, and the rockers so the tire would stop scrubbing.

well I got out of the car when it still scrubbed to see what it was doing. So the car looks like it loads up and the body separates from the tire on the side you’re turning towards and it moves the tire towards the front of the car and hits the rocker. The car is sitting much higher now than before, like 2-3”. We changed shocks to make sure they weren’t the problem cause it felt so stiff we thought they froze up. That wasn’t the problem.

my thoughts are the torque arm somehow has the rear end “preloaded” somehow and it’s causing these issues. I’ve just never had this problem before so it’s kind of odd. The lcas are both tight.

 

Rear steer is usually caused by lower control arm angles.

 

right now the lca is on the lowest hole on the quick performance 9”. He’s going to mess with it today and change the location and see if it changes. If I jack up the car on the frame rail the wheel starts moving forward and makes contact with the rocker. also going to check pinion angle to make sure the torque arm isn’t in some weird position.