I have run into this problem before. (I bought a set of 4 1/2 wheels from a fabo member who said they were 5 1/2... Determining if a wheel is a 5 1/2 or a 4 1/2... My understanding is that the 4 1/2 were standard including on V8 cars. My guess is you have the 4 1/2 wheels. The 5 1/2 wheels came on performance cars like the GT and Formula cars.
I know what I have. You can also tell by the offset of the wheel if you know what you are looking at. Look at the lip of the 4 1/2 wheel that you have and look at mine. Mine have a deeper offset.
