tolerance issue?

[BJDEALER]

Ok I have been fitting tires on a pair of 15x7 cop wheels on my 66 barracuda. I have replaced the stock rear with an 8 1/4 out of a 74 dart. I put a 225/60/15 tire on the driver side rear to try out. I have less than 1/2 an inch clearance between the quarter panel and tire. it doEs not rub though. On the other side when I put the same size tire and I have at least an inch clearance. Is there a good reason for this? Could the tolerance from side to side be off that much? How can I get more room on the driver side?

 

[2manymopars]

I have the same issue on a 65 with a late 8 1/4, just not quite as bad. Check all your bushings as a worn bushig will cause this. One thing to try would be to loosen the U bolts have someone apply pressure to the left side while you tighten the U bolts.

 

[65cuda360]

The rear end is not centered on many cars.

 

[RedFish]

The wheel base is staggered for a few reasons. The engine torques right on the chassis which is one of the reasons for the rear axle offset.
Those who drag race only and want the car to launch straight ahead do all sorts of things including altering spring hangers. You can do that too if you want.
To fully appreciate the drive line angle, thrust angle, ackerman angle, and more that goes into building a street vehicle, the average Joe would probably need to build one perfectly square then start making those changes that make it work right.

 

[67Dart273]

You might have 1/4" or more "slop" in the center bolts. Loosen the U bolts, see if you can move the axle at all towards the loose side and retighten. Might also be a little in the rubber bushings. These cars were never made to very tight tolerances.

 

[66 Dartman]

Out of all the A bodys i have swaped diffs in all were different,As long as it's square
between your rails your good, As said above tolerances were **** back then.