I have 17x8.5" +56mm offset ZR1 wheels with 255/45/17 Nitto NT555s coming for the front of my car. Currently have stock brakes but will be going with C5 fronts in the coming month or two. Will the rims fit in the meantime with a 1.7" spacer? I have to drive the car in the meantime with the new rims and I don't want to have to buy 2" spacers now and then 1.7" spacers once I get the C5 brakes.

Since people are running 275 rubber on 9.5" wheels with 2" adapters in the front, I figured the 8.5" wheels with 255 rubber will work fine with 1.7" spacers because there is about a half inch difference in backspacing between the 9.5" w/ 275 and the 8.5" w/ 255 and the difference between 1.7" adapters and 2" adapters is only .3". If I'm correct about this, then the 8.5" rims on 1.7" adapters will actually clear better than 9.5" rims on 2" spacers. If you're gonna say .3" isn't noticeable, go away. My main concern is keeping the centerline as close to stock as possible once I get the C5 brakes. For now, I just want to be able to drive the car.

Unless I'm wrong about people running the 9.5" rims with 2" spacers and they're actually using the 2.25".

 

I am not sure what my real ZR1 backspacing is but after my ls1 front brake upgrade I am only using a 1 1/4 spacer with 275/40/17