This kit is basically the same set-up that S uses in their SH-series \'Shovelhead\' engines. It enables you to upgrade your Shovelhead to the more modern Evo style valve train. Kit includes S Evo style tappets, billet aluminum CNC machined tappet guides, adjustable Quickee pushrods, gaskets, hardware and pushrod cover keepers. Compatible with OEM or OEM style rocker arms. Note: A 84-99 style Evolution Big Twin cam must be used.