ive got a set of z06 wheels and tires, front are 275 on 17's rear are 295's on 18's, my question is what size wheel adapters should i run on the front and rear? i want to keep the wheels in the fender wells, ive got an 86 base firebird, and im running a swapped in 9 bolt with disc brakes.

 

We need to know the offset of the wheels in order to tell you the correct sized spacers.

 

If they are REAL FACTORY Z06 wheels, then you need 2" all the way around.

If they're aftermarket knock-off look-alikes that merely resemble Z06 wheels stylistically, then who knows. All bets are off since anybody can cast wheels that look like anything, and make the offset anything they feel like, within the physical possibilities allowed by whatever they "look" like; and they usually do. As said, you need the measurements FOR YOUR PARTICULAR WHEELS in that case, in order to know.

 

2 1/4" for the fronts, 2" for the rears.

You need the extra 1/4" on the fronts for the tie rods. OEM ones are a little different than my MOOG ones.