ARP Main Stud kits eliminate main cap walk and fretting, as well as protect the threads in your engine block. All kits come complete with hardened parallel-ground washers and high quality nuts. The studs are manufactured from 8740 Chromoly steel, heat-treated in-house to 200,000 psi tensile strength, and precision J-form threads rolled after heat-treat to create a fastener that has threads 1000% stronger than others.
ARP recommends the use of main studs over bolts whenever possible for several key reasons. First is the ability to obtain more accurate torque readings because studs don’t “twist” into the block. All clamping forces are on one axis. By the same token, there is less force exerted on the block threads, which contributes to improved block life (very critical on aluminum blocks). Finally, there are factors of easier engine assembly and proper alignment of caps every time.
Large Journal ONLY - Hex Head Nuts