Patent ID: 7040264

Claim:
An internal combustion engine comprising: a cylinder, a crankshaft, and a piston connected by a connecting rod to the crankshaft and being movable with reciprocating motion within the cylinder upon rotation of the crankshaft, the piston motion providing a succession of four strokes including an induction stroke, a compression stroke, a power stroke and an exhaust stroke; an intake valve and an exhaust valve located in the cylinder, wherein the intake valve serves to admit gas during the induction stroke into the cylinder, and the compression stroke serves to compress a quantity of the gas within the cylinder in preparation for the power stroke, the gas being a mixture of air and fuel in the case of a gasoline engine, and air without fuel in the case of a diesel engine; a timing device synchronized with rotation of the crankshaft for operating the exhaust valve to provide for an interval of closure of the exhaust valve and an open interval of the exhaust valve, an opening of the exhaust valve permitting an exhausting of exhaust gas from the cylinder, wherein the open interval of the exhaust valve extends over a terminal portion of the power stroke and into the exhaust stroke, and wherein a starting point for the opening interval of the exhaust valve is taken at the instant when the exhaust valve has risen 0.050 inches from the valve seat; and wherein the timing device is operative to advance an opening of the exhaust valve prior to a power advancement interval in the terminal portion of the power stroke; and wherein an advancing of the timing of the opening of the exhaust valve to coincide with the power advancement interval provides for a maximum power output capability of the engine with a reduced value of efficiency of the engine, and the opening of the exhaust valve prior to the power advancement interval provides for an increased value of the efficiency and a reduced value of the power output capability of the engine.