Newbie rear susp question

[goa484]

Hi, I just got into doing some handling mods on my gto. I have adjustable upper and lower control arms on the rear that seem to be equal in length but I have the passenger tire about 3/4" closer to the quarter panel than the drivers side. Could just be a body issue but I was wondering what techniques you guys use to make sure that the rear is centered and square with the chassis. I also seem to have a slight left pull but only under moderate to heavy acceleration.
Thanks!

[raustinss]

Make sure that the upper arms are the same length.....also double check the length of the bottoms. You could do some quick measurements of body to frame...this will help with identifying if it's the frame or body. If the body is sitting square on the frame . You can also spend a few hundred $$$$ and get the car put on a rack at a body shop, they'll be able to tell you right quick what's wrong best of luck
Ryan Austin

[TheJDMan]

How long have you owned this car? Do you know the history of this car? Has this car been in an accident at some point in the past? It sounds like the frame could be tweaked. It might be worth a trip to a frame shop and have it checked for square.

[goa484]

Originally Posted by TheJDMan

How long have you owned this car? Do you know the history of this car? Has this car been in an accident at some point in the past? It sounds like the frame could be tweaked. It might be worth a trip to a frame shop and have it checked for square.

I've owned it for about 13 years and had the frame checked awhile back. I had a shop put the suspension on and they messed it all up. I had one control arm about half an inch different than the other and found numerous nuts not torqued (one of my uppers was finger tight!). I was able to move the rear over to the left by getting the arms equal and probably could get it so the wheels are centered in the wells, but I'm more worried about the thrust angle being correct and not dogtracking down the highway. Right now, the car seems to track straight until I really get on the throttle than it moves just slightly to the side.

[DETON8R]

Did you do a good measurement of the third member and verify the set-up on the third member? Often the pumpkin is offset from center to make sure the drive line has a few degrees offset.

Did the shop set up the rear end based on the pumpkin location or the true center of the third member (based on the hubs)?

[goa484]

Originally Posted by DETON8R

Did you do a good measurement of the third member and verify the set-up on the third member? Often the pumpkin is offset from center to make sure the drive line has a few degrees offset.

Did the shop set up the rear end based on the pumpkin location or the true center of the third member (based on the hubs)?

Not really sure what the shop did. Pardon my ignorance but what is the best way to do this measurement? What am I looking for? Rear is 8.2 BOP.