An opposed piston engine, comprising: a cylinder having an inlet port and an exhaust port disposed on opposite sides of a centerpoint of the cylinder in an axial direction of the cylinder; an inlet piston arranged to reciprocate in the cylinder between an inlet piston bottom dead center position (IPBDC) and an inlet piston top dead center position (IPTDC), the inlet piston closing the inlet port when the inlet piston moves through an inlet port closed position (IPCP) as the inlet piston moves through at least a distance of an axial height of the inlet port from IPBDC toward IPTDC and the inlet piston opening the inlet port when the inlet piston moves through the IPCP as the inlet piston moves from IPTDC to IPBDC; an exhaust piston arranged to reciprocate in the cylinder between an exhaust piston bottom dead center position (EPBDC) and an exhaust piston top dead center position (EPTDC), the exhaust piston closing the exhaust port when the exhaust piston moves through an exhaust port closed position (EPCP) as the exhaust piston moves through at least a distance of an axial height of the exhaust port from EPBDC toward EPTDC and the exhaust piston opening the exhaust port when the exhaust piston moves through the EPCP as the exhaust piston moves from EPTDC to EPBDC; an inlet piston crankshaft arranged to rotate about an inlet piston crankshaft axis of rotation and connected to the inlet piston by an inlet piston piston rod; and an exhaust piston crankshaft arranged to rotate about an exhaust piston crankshaft axis of rotation and connected to the exhaust piston by an exhaust piston piston rod, characterized in that the inlet piston crankshaft axis and the exhaust piston crankshaft axis both extend parallel to a central cylinder plane extending through the centerpoint of the cylinder and along a central axis of the cylinder, in that the inlet piston crankshaft and the exhaust piston crankshaft are arranged to rotate in phase, and in that the HIP and the HEP are selected and the inlet piston crankshaft axis and the exhaust piston crankshaft axis are both offset from the central cylinder plane such that the inlet piston moves through the IPCP as the inlet piston moves from IPBDC toward IPTDC at substantially a same time as the exhaust piston moves through the EPCP as the exhaust piston moves from EPBDC toward EPTDC whereby the exhaust piston closes the exhaust port before the inlet piston closes the inlet port resulting in a lead of no more than about 3 crank angle degrees for the exhaust piston crankshaft relative to the inlet piston crankshaft. a cylinder having an inlet port and an exhaust port disposed on opposite sides of a centerpoint of the cylinder in an axial direction of the cylinder; an inlet piston arranged to reciprocate in the cylinder between an inlet piston bottom dead center position (IPBDC) and an inlet piston top dead center position (IPTDC), the inlet piston closing the inlet port when the inlet piston moves through an inlet port closed position (IPCP) as the inlet piston moves through at least a distance of an axial height of the inlet port from IPBDC toward IPTDC and the inlet piston opening the inlet port when the inlet piston moves through the IPCP as the inlet piston moves from IPTDC to IPBDC; an exhaust piston arranged to reciprocate in the cylinder between an exhaust piston bottom dead center position (EPBDC) and an exhaust piston top dead center position (EPTDC), the exhaust piston closing the exhaust port when the exhaust piston moves through an exhaust port closed position (EPCP) as the exhaust piston moves through at least a distance of an axial height of the exhaust port from EPBDC toward EPTDC and the exhaust piston opening the exhaust port when the exhaust piston moves through the EPCP as the exhaust piston moves from EPTDC to EPBDC; an inlet piston crankshaft arranged to rotate about an inlet piston crankshaft axis of rotation and connected to the inlet piston by an inlet piston piston rod; and an exhaust piston crankshaft arranged to rotate about an exhaust piston crankshaft axis of rotation and connected to the exhaust piston by an exhaust piston piston rod, characterized in that the inlet piston crankshaft axis and the exhaust piston crankshaft axis both extend parallel to a central cylinder plane extending through the centerpoint of the cylinder and along a central axis of the cylinder, in that the inlet piston crankshaft and the exhaust piston crankshaft are arranged to rotate in phase, and in that the HIP and the HEP are selected and the inlet piston crankshaft axis and the exhaust piston crankshaft axis are both offset from the central cylinder plane such that the inlet piston moves through the IPCP as the inlet piston moves from IPBDC toward IPTDC at substantially a same time as the exhaust piston moves through the EPCP as the exhaust piston moves from EPBDC toward EPTDC whereby the exhaust piston closes the exhaust port before the inlet piston closes the inlet port resulting in a lead of no more than about 3 crank angle degrees for the exhaust piston crankshaft relative to the inlet piston crankshaft.