The S&S T143 Long Block engine is the largest S&S engine that will fit in a stock Harley- Davidson chassis. At double the HP of a stock motor, the power of the T143 requires technical expertise for the installation and tuning along with an experienced rider. This is an ultra performance/race engine. Longevity, engine noise, vibration and throttle sensitivity have all been compromised to reach this level of performance while fitting in a stock chassis and, as such, is not suitable for every situation. It is the purchasers responsibility to consider the suitability for their application. Engine noise and damage from abuse is not covered under warranty. Fits in stock chassisno cutting or frame modifications. S&S B3 cylinder heads CNC-machined with 2-bolt exhaust flanges. 3 Piece Flywheels. S&S high flow oil pump and cam cover. S&S 635 Easy Start Gear Drive Cams and S&S 1.725:1 rocker arms for .674 in. total lift. S&S Premium High Performance Tappets. Made in USa. NOTE: Does not include carb/ intake or ignition system. Must be purchased separately. NOTE: T143-specific or custom exhaust required.