What is the difference between 6 and 7 bolt head studs? I swore I bought 7 bolt head studs and the box looks exactly the same as a box of 6 bolt ARP's. The part numbers are 207-4201 and the upc's are 672036008109. Can anyone confirm this? Are these also 6 bolt ARP's?

One is 1mm bigger than the other.

Ok, thanks. I quess I have a 6 bolt and a 7 bolt laying in the garage now (just thought of it). Quess I can go check and see what fits each.

207-4203 = 7 bolt, 207-4201 = 6 bolt.

Cool, thanks.