A four stroke internal combustion engine with dedicated exhaust gas recirculation and method of operating such engine, wherein the engine comprises a plurality of combustion cylinders including main cylinders and a dedicated exhaust gas recirculation cylinder, wherein each cylinder includes a piston; a crankshaft, which is rotatable in a direction, and defines a main crankshaft axis, and includes a plurality of crankpins. Each of the crankpins is coupled to at least one of the pistons. The crankpins affixed to the pistons of the main cylinders are spaced at an interval around the main crankshaft axis. The crankpin affixed to the piston of the dedicated exhaust gas recirculation cylinder is spaced at an offset of 5 to 50 degrees from the interval in either direction relative to the direction of crankshaft rotation.
Raphael Gukelberger; Steve H. Alamaraz