If you have ever installed a rocker stud into a cylinder head and watched it wobble as it screwed in ? you knew from the beginning that the rocker geometry was going to be inconsistent all over the place. ARP rocker studs are concentric within .005 T.I.R. thread pitch to thread pitch. They run-in straight and true. Lengths are exact ? designed to provide positive seating every time. An extra-large radius base offers greater resistance to flex. Available in both High Performance and Pro Series models. NOTE: Not to be used with OEM-style, self-locking nuts. To be used with ARP?s patented Perma-Loc? adjusters HIGH PERFORMANCE SERIES
Made of 8740 chrome moly forgings and heat-treated to 180,000 psi. Excellent for E.T. Bracket Racing, limited rule oval track competition and street use. Tip ground flush for optimum adjuster seating. PRO SERIES
Designed for competition applications, ARP?s Pro Series rocker arm studs are made of premium grade 8740 chrome moly steel and heat-treated to a tensile strength of 200,000 psi.