Quick view ARP ARP- Cylinder Head Studs, Pro Series, Hex Head Nuts, Ford, 4.6, 5.4L, 3-Valve 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. The Pro series kits are also available with 12-point nuts, and all kits... MSRP: $501.67 Add to Cart The item has been added Compare