10 With stock camshafts, the factory Chrysler stamped steel rocker arms can be used with the E-Street heads. With higher than stock lift camshafts, Edelbrock recommends adjustable rocker arms. We ordered a set of Ultra Pro-Magnum rocker arms from Comp Cams to install on our 383. Comp’s 1.5 ratio Pro-Magnum rockers offer a roller tip, are bushed where they ride on the rocker shaft, and a cup-style adjuster on the pushrod end. We also ordered a set of Comp’s Hi Tech pushrods with ball-ball ends and installed them with the rockers, setting valve lash at zeto plus one turn for our hydraulic lifters.