T124 Low Compression Long Block EngineIncludes Super Stock™ heads, T2 crankcase, high flow oil pump, cam cover and easy start 585 gear drive cams No fuel system or ignition systems included Special head machining fits stock length intake manifolds (S&S manifold size 405) Stock style breathing system; compatible with stock and most performance air cleaners Oil line installation kit required. Cylinder heads on T-Series long block engines are '99 - '05 style. Owners of '06 models will need to purchase a set of '99 - '05 style, offset intake flanges. Cylinder heads on these engines are specially machined to compensate for the non-stock cylinder length. As a result, they are compatible with manifolds and throttle bodies with stock length intake runners. In addition, the breather vent bolt locations have been adjusted so they are in the stock location, so stock style air cleaner back plates will bolt up to these engines.