How do I get my rear gta wheels to fit on a 4th gen rear?

 

You don't.

Unless you know where to get a spacer that takes space out, instead of putting space in.

You have to move the center of the wheel hub about 2" toward the outer edge of the wheel. Look at your wheels. If you can figure out a way to do that, you can become a VERY rich man. I'm sure that such a technique would have many applications beyond your immediate need.

 

They bolt on as long as the brakes will clear(LS1 13" set-up might not clear a GTA wheel?) - but as sofa stated, the 4th gen rear is almost 2" per side wider, so you wheels will stick out almost 2" per side from where they are now. - Some like it, some don't(IMO - ok with GTA/IROC wheels, hill-billy with other factory wheels). They sit square with the upper lip of the wheel well(been there, done that). - If you do a search under my name about wheels, you'll find pics of my 11" rears. The outer offset is the same as my factory wheels, the 3" width was added entirely in back-space.

 

Let's clear some stuff up.

You need a 2" spacer that can be bought from people on this board in the classifieds, or on Ebay.

The 4th gen rear is about 2" wider total, not 2" per side.

LS1 brake rotors are 12" (actually 11.8" or something) and fit 16" rims.

 

Wrong.

That's what you need for putting 4th gen wheels on a 3rd gen rear.

You need a -2" spacer to go the other way, the way he wants to go: 3rd gen wheels on a 4th gen rear.

Also wrong.

The 4th gen rear is actually about 1-5/8" wider per side.

I've heard about problems with the GTA wheels clearing various brakes also, that other wheels don't have; evidently they're more sort of cone-shaped inside the rear, where others are more of a cylinder. But I have no personal knowledge of that, I'll gladly defer to someone with experience in that matter.

 

3rd gen WHEEL to 4th gen AXLE

Was thinking 4th gen wheel to 3rd gen axle.

Ok so it's a little over 3" longer, same difference.

I know I'm right about the LS1 brakes though

 

I'll agree on the LS1 brakes.
1-5/8, I'll buy that. - I said almost 2".....

The GTA wheels are regular cylinder type wheels, but the have a lip on the inside(just like the outside) and won't clear on some brake set-ups that IROC and some of the other 16" wheels will.

 

Damn. Im never givin up my gta wheels!!! well not till their on atleast two more cars So Ill look into a 3rd gen rear with posi

 

if you stay 10-bolt, look for the later ones(like 89 and newer) that way you get 28 spline axles instead of the 26's.