Stage I : Assembled with Stainless Steel Valves, with a complete valve job, Manley chrome-moly retainers and locks, Viton valve stem seals and Isky double valve springs for up to .570 lift cams. (Optional valve springs are available for any lift cam. Call for pricing.)
Stage II : Includes Stage I plus pocket porting, intake port match and port clean up as well as full exhaust porting.
Stage III : Includes Stage I & II plus full intake porting, reshape chambers to enhance flow around the valves, and polish combustion chambers.