Using COMP Shaft Mount Rocker Systems is one of the most effective ways to increase horsepower. These systems transfer the power of the camshaft to the valve by properly positioning the rocker over the valve. Constructed from 2024 aluminum and using an 8620 hardened steel shaft, COMP shaft rockers are designed using the latest in computer technology and are field tested by experts in every type of racing. * Made from 2024 aluminum and use 8620 hardened steel shaft * Most efficient way to transfer the power of the cam to the valve * Rigidity of the shaft system adds stability to the cylinder head and the valve train * Use an oiling system that ensures consistent oil flow from the pushrod cup to the shaft bearings and then on to the roller tip PartNumber : cca1503 Description : Shaft Mount Aluminum Rocker Arm Title : 1503 Shaft RKR, SBC Dart Iron Eagle , 1.6/1.5 California Proposition 65 : WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov Engine Family : Chevrolet 262-400 c.i. 8 Cylinder (1958-1998) Exhaust Offset : 0.17 Exhaust Rocker Arm Ratio : 1.5 Intake Offset : 0.17 Intake Rocker Arm Ratio : 1.6 Rocker Arm Material : 2024 Aluminum Rocker Arm Series : Shaft-Mount Aluminum Rocker Stud Diameter : Shaft Ratio : 1.5 Stud Diameter : Shaft Engine Components::Rocker Arms