Competition Cams 19024-16 Ultra-Gold Aluminum Roller 1.7 Ratio, 8mm Stud Diameter Rocker Arm for LS Series Engines CNC-machined, lightweight design removes weight and yields unrivaled quality and ratio accuracy Designed for high performance street and race engines;Exclusive spiral lock type clips replace retaining clips for improved durability Precision-sorted trunion bearings withstand elevated valve spring pressure and valve lift Additional clearance, up to 1.650 inch O.D. valve spring