ARP Honda D16A / Z Head Stud Kit - 208-4301. Complete with Studs, Washers, and Nuts ARP Head Stud Specs made out of premium 8740 alloy rated far superior to aircraft quality Heat treated to 200,000 psi Thread Rolled after heat treat (1000% better than studs that are thread rolled prior to heat treat Some Technical info on Studs Using studs will make it much easier to assemble an engine( especially a racing powerplant which must be serviced frequently and quickly!) with the cylinder head and gasket assured of proper alignment. Studs Provide more accurate and consistent torque loading ( When you use bolts to secure the head, the fastener is actually being twisted while it's being torqued to the proper reading. acordingly, the bolt is reacting to two different forces simultaneously. A stud should be installed in a relaxed mode - never crank it in tightly using a jammed nut. If everything is right, the studs should be installed finger thight. Then, when applying torque to the nut, the stud will stretch only on the vertical axis.