These superior quality chromoly rockers are just the answer for either a mild street or a hi-performance competition engine. EMPI's rocker arms are made from forged chromoly and then precision ground and heat treated. Not only are these the strongest rocker arms available, they are also drilled through on the alloy adjusting screws so both screws and rocker arms are fully lubricated. All shafts, blocks and shims are high strength alloy as well. Precision ground bronze bushings with through hole lubrication ensures that premature failure of the old needle bearing rocker arm design is a thing of the past. Chromoly rocker arm studs are provided to complete this kit and make installation and use a trouble free experience. Requires P/N: 4034 Cut-to Length Pushrods to set valve train geometry and achieve the correct pushrod length.