High Compression, 10.8:1 for the ultimate in street performance. No fuel system or ignition systems included. Special head machining fits stock length intake manifolds (S&S manifold size 410). Stock style breathing system; compatible with stock and most performance air cleaners. Includes Super Stock heads, crankcases, high flow oil pump, cam cover and easy start cams. Black Edition includes all the features of standard S&S engines, with gloss black engine covers in place of the standard chrome covers. Made in the u. s. a. NOTE: 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 aircleaner back plates will bolt up to these engines.