Guys I know if you want to put 15 inch welds on the back of one of these cars you have to grind the calipers some, but I was wanting to know is whats the widest rim and offset I could use on this and what size tire can I use? Thanks:confused:

Im not sure of the off set but I have seen 315's on an 11 in rim. They might rub just a tad. The most common fix I have seen is to beat the inner part of the wheel well some.

Check out this link, it should answer your questions pretty good.

http://www.camaroz28.com/forums/forumdisplay.php?f=49

With a 15x10 7.5"BS you can run a 325/50-15 with some massaging of the inner fender & possibly adjustable control arms to center the axle front to rear in the opening.