The 124 cubic inch T124 low compression Long Block engine fits 1999-'06 HD big twins except 2006 Dyna models. Long Block engines do not include a fuel or ignition system, so they can be used for either carbureted or EFI applications. If you already have a performance ignition, larger carburetor or a larger throttle body and EFI tuner, they can be used with this engine. The cylinder heads are specially machined to compensate for the longer cylinders so a stock length manifold or throttle body will fit perfectly, and the cylinder head breathers are compatible air cleaners designed for a stock engine. Engine features 4-5/8" stroke X 4-1/8" bore at 10.2:1 compression, S&S 585 gear drive Easy Start cams, S&S TC3 cam plate and oil pump, and silver powder coat finish that matches stock engine components.

• Stock non programable engine management systems should not be used because they are not designed for an engine this large
• T series engines are not compatible with HD Softail models
• This engine has slightly less compression than a S&S high performance T124 engine, making it more tolerent of variations in fuel quality, and a better choice for heavier vehicles
• Two year warranty