This 93 cubic inch S&S SH93 engine fits 1970-84 HD big twin models and is ideal for a building a retro custom bike. Features and benefits • Natural crankcases and black powder coated cylinders • S&S 8.5:1 forged pistons and S&S Super Stock cylinder heads • S&S billet cam cover • S&S hydraulic valve train and roller rocker arms • S&S Super Stock™ single fire ignition system • S&S Super carburetor with classic teardrop air cleaner • Two-year warranty