Here's a way to give your 3-5/8" bore shovelhead engine the nostalgic look of a pan, and improve performance at the same time. The Retro Cylinder Head and Valve Train Upgrade Kit consists of a set of S&S P-Series 3-5/8" single plug cylinder heads with rocker cradles, S&S roller rocker arms, S&S hydraulic tappets, billet tappet guides, Quickee pushrods, pushrod cover clips, and the required gaskets and hardware for assembly. Fits 3-5/8" bore engines in Harley-Davidson motorcycles.