Filling out the heads are relatively small 2.00-inch intake valves, and 1.55-inch exhaust valves, though the size was plenty for a 305's small 3.736-inch bore. The valvetrain was stepped up with COMP's No. 918 beehive springs, PRW 1.65:1 self-guiding rockers, and PRW pushrods. Lifters are COMP No. 2900 solid flat-tappets.