From the factory, our Edelbrock heads were supplied with 7/16-inch rocker studs. However, our Comp Cams rockers would only fit 3/8-inch studs. Luckily for us, ARP had the studs (PN 134-7101) needed to convert our 7/16-inch studs to the smaller 3/8-inch to fit the rockers. Using an 11/16-inch socket we removed the original studs. For the ARP studs, which penetrate the intake ports, we used thread sealer while the others we used some ARP moly-lube. We torqued the studs to 55 ft-lb with an 11/16-inch socket.