Corvette C3, 1978/79. What is the original offset on the stock slot wheels?

If you go to a well versed rim/tire dealer, they have all the specs for your car. My C-3 came with 15" rims and I was able to fit wider tires on it in the 60 series. I have seen 16" to 17" but had to stick with the 60 series tires to prevent rubbing on the fenders or frame in the front when turning. Too wide on the rear and the brake hose bracket will cut the tires. There are ways to get wider tires under the fenders and taller rims. The A-arms can be changed out with ones that are curved to fit the wide tires. Fender flares, ala L- 88 design works also. I used those, but modified them to fit the tires sticking out the rear, and put on American Racing 200S rims, 15".

Different angle.

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