ARP Cylinder Head Bolts
High Performance Series:
ARP High Performance head bolts are available with a reduced wrenching hex or 12 point and a wide flanged head that eliminates the need for valve train removal to facilitate cylinder head retorquing. All high performance series bolts are 180,000 psi (Which is 15% stronger than grade 8) and kits come complete with hardened parallel ground washers.
All pro series bolts are cold forged to ensure molecular integrity, heat treated prior to thread rolling and machining, and are rated nominally at 200,000 psi. ARP Pro series head bolts are application specific - designed for use with typically competition only components. These fasteners deliver superior strength and meet the ARP "Zero Defect - Zero Failure" quality standard. Hardened and parallel ground washers are included with each kit to ensure even load distribution and accurate torque readings. All pro series bolts have a reduced wrenching 12 point head and wide flange area to eliminate the need for valve train removal for cylinder head re-torquing and permits the use of large diameter valve springs. most applications have undercut short bolts that can help eliminate head gasket failures through providing more stretch to compensate for additional compression of gaskets.