73 dart wheel size?

I think you will find that if it is a 6 cyl it will be 4" bolt circle and if V8 it will be 4 1/2" bolt circle. I have a 74 parted out and it is a 6 cyl and has 4" circle. I thought after 72 the bolt pattern went to 4 1/2", but some one told me the reason my 74 was small bolt pattern was because it was a 6 cyl.