if you want the 3.5 inch studs its a .625 knurl they can be found at summit for 12.95 for a set of 5 http://store.summitracing.com/partde...t=ARP-100-7703
and you need a 39/64 drill bit
if you want the 3.5 inch studs its a .625 knurl they can be found at summit for 12.95 for a set of 5 http://store.summitracing.com/partde...t=ARP-100-7703
and you need a 39/64 drill bit