Abstract: In one embodiment, an improvement to a four-stroke engine having a single cylinder block arrangement including an engine block, timing gears, crankshaft and gear, timing belt/chain, intake port, exhaust port, and cylinder head arrangement includes a ported rotating shaft, the ported rotating shaft having a first port, the ported rotating shaft synchronized with the crankshaft, such that the first port periodically aligns with the intake port to allow for intake during the four-stroke cycle.