An overhead
rotary valve fitted into a
cylinder head with diametrical polygonal openings formed therein for use in combination with an
internal combustion engine, driven to bring intake and exhaust ports into and out of alignment with passages leading to and from the
combustion chamber. Sleeve bearings are fitted in the
cylinder head that provide surface sealing, and annular sealing members prevent the air / fuel mixture or exhaust gases from flowing into regions intermediate ports and individual cylinders. Utilizing this overhead
rotary valve and associated seals and bearings increases the efficiency and performance of an
internal combustion engine. The overhead
rotary valve rotating, at one quarter the speed of the
crankshaft, minimizes wear and
noise levels, self cleans the ports, allows the engine to operate at higher rpm and imparts proper opening and closing of passages at the proper sequence of
valve timing without concern of
valve float. The instant invention removes the need for reciprocating intake and exhaust valves, camshafts, rocker arms, lifters, push rods, valve guides and retainers, and other related hardware for actuation, significantly increasing the reliability and effectiveness of the
internal combustion engine, while reducing overall manufacturing costs.