HP Series Cylinder Head Studs - Small Block Chevy
High Performance head bolts are available with a
reduced wrenching hex or 12-point and wide area flanged head
that eliminates the need for valve train removal to
facilitate cylinder head re-torquing. All High Performance Series
bolts are 170,000 PSI (which is 15% stronger than Grade 8)
and kits come complete with hardened parallel-ground washers.
Premium grade 8740 alloy that is rated far superior to "aircraft" quality. Then, each stud is precisely heat-treated to 200,000 psi. ARP studs are thread rolled after heat-treat, which gives them about 1000% (that's ten times) better fatigue strength than those studs that are threaded prior to heat-treat (a very common industry practice). All kits come complete with hardened parallel-ground washers and high quality nuts. ARP offers specially undercut studs for several engines. This procedure (done only to the shorter studs) more equalizes the "stretch" of both studs, which makes for a more consistent clamping force and one that compensates for head gasket compression when the cylinder heads are installed. This helps prevent blown head gaskets, and assures optimum engine sealing!