These ARP High Performance series head bolt kits are tough! They are rated at 170,000 psi--15 percent stronger than Grade 8 fasteners. They come available with hex heads or reduced wrenching 12-point heads that eliminate the need for valvetrain removal when re-torquing cylinder heads.

These Pro series studs from ARP are cold-forged to ensure molecular integrity. They are heat-treated prior to thread rolling and machining and are rated at a whopping 190,000 psi.

These Pro series studs from ARP are cold-forged to ensure molecular integrity. They are heat-treated prior to thread rolling and machining and are rated at a whopping 190,000 psi.