Okay before someone gets all crazy with the "learn to search", I looked into all this before attempting this.

As stated I have an 86 IRoc that I put a 4th gen firehawk 10 bolt under the rear. I have C6 rims and tires that I got from a friend. Everywhere I found said it should be a direct bolt on. The problem is that on the drivers side the tire rubs in the wheel well on the inside sidewall of the tire. After some looking I found that some 4th gen rears were slightly more narrow? I assume my only fix would be wheel spacers. Should I get a wheel spacer and buy bigger studs, or get one of the wheel spacers that bolt on and use new studs? Anyone suggest a good brand? Anyone else have this problem, or use wheel spacers with C6 rims and know which set will for sure clear the rim? Thanks in advance for the help.

 

Where did you find info about some 4th gen rears being more narrow ???

I only have (4) 4th gen rears for reference, BUT they are all the same width

I would guess that you are going to have to go with bolt on spacers (much better option than LONG studs and slip on spacers)

http://wheeladapters.us/

~DaVe

 

I had read somewhere that the 4th gen firehawk's rear end was 2 inches narrower then other 4th gens. I have not measured it yet. The rear seemed normal. (My stock tires stick out just as much as any of the pics I have seen) Also thanks a ton for the link. The adapters I had my eye on (summit) were $188.

 

Ok, so I got spacers for the rear. Those fit nice. Now I'm wondering, what size spacers do people use on the front? Some places I see 1.25 others say 2.

 

Why don't you just slap them on and see what works best for you? Or take a ruler and measure it.

 

I have a pair of wheel spacers for sale that I used for my 96' SS wheels, i believe they were 2" but i can double check and get pictures if your interested. $100 shipped

 

IIRC, an LS1 rear end is like 3/8" wider total than an LT1 due to the difference in brakes, more specifically the parking brake. So, while not really an issue as a practical matter, the OP is technically correct. An adjustable pan hard might also be of value. I think the problem is OEM and most repop 19" rear wheels have HUGE backspacing so the "normal" guidelines might not apply.