These ARP High Performance series connecting rod bolts are made from seamless and defect-free 8740 chromoly steel. All ARP rod bolts are heat-treated before grinding and thread rolling and have a large underhead radius for greater strength.
Pro series cylinder head 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 220,000 psi.
These ARP main studs are made from 8740 chromoly steel and have a 200,000 psi tensile-strength rating. They are precision centerless-ground and thread-rolled to Mil-S-8879 specs, with a black oxide finish for corrosion resistance.