I just bought some new black Z06 wheels and they're 17x8.5 with 56mm offset in the front (should be 2 in. spacer required) and 17x9.5 with 38mm in the rear, is that right? Why the smaller offset in the rear? Have I been had?

38 mm offset equals 6.7 backspace . Your in good shape with a spacer. Tohse are the low offset version.2 inch adapter will work.
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go to skulte.com and click on FAQs and there is a chart for ya.

yeah I checked out the chart, it doesn't make much sense to me (he loses me with 2+50mm) But I did e-mail him once and he got back to me that day with an answer. I bought these wheels from a guy with a 4th gen camaro that sold the car before he got a chance to use them, so these should be a direct bolt on to 4th gen? In that case I should be able to run a 4th gen rear (or 2" spacer) and 2" spacer up front? I thought the rear wheel with 56mm offset required 2" spacer\

got it figured out, tard question