Small or big bolt pattern

I have 15" ralleye wheels on my small bolt car. Not sure of exact measurments, but if you have the 7 1/4 rear you would have the small bolt set up. I think the 8 3/4 rears also carried a small bolt for a couple years , but all 8 1/4 should be large bolt. I think this is correct if not I am sure someone will have something better.