I have a 92' z28 with a 97' 4th gen rear. It's definitely 2" wider on each side as I had 18x10.5 z06 out back with no problems. I plan on getting a set of 19x10 rims with 285 or 295 tires. What offset can I use for the 19x10 rim, 56mm? Thanks in advance.

 

What offset were you using with the 10.5" wide Z06 wheels? Given that, the new 10.0" width, and the EXACT overall width change on the rear axle assembly, its a simple mathematical calculation to put the new wheels exactly where the old wheels were (assuming they were satisfactory).

 

I don't the offset on the old setup. I gambled and purchased it not knowing the idea of offset. I was basically lucky. Judging by the sticky above it seems that 56mm is the way to go.