Abstract: A compression ring for an engine piston includes an upper and lower face, and an inner face positioned between the upper and lower faces along an inner diameter of the ring. An outer face is positioned between the upper and lower faces along an outer diameter of the ring and is formed by a continuous curve along the axial direction of the ring. The continuous curve has first and second convex surfaces connected by a concave surface with each convex surface defined by first and second radii, respectively. A method of forming a piston compression ring includes machining an outer face of the ring to form a continuous curve along an axial direction of the ring, where the continuous curve has a first convex section and a second convex section connected by an intermediate section.

Abstract: A crankshaft in an engine is provided. The crankshaft includes only two outer bearing journals configured to attach to two outer crankshaft bearings, only a single inner bearing journal positioned axially between the two outer bearing journals configured to attach to an inner crankshaft bearing, an unsupported section positioned axially between the inner bearing journal and one of the outer bearing journals, and only three rod journals each configured to attach to a separate piston rod.

Abstract: A crankshaft in an engine is provided. The crankshaft includes only two outer bearing journals configured to attach to two outer crankshaft bearings, only a single inner bearing journal positioned axially between the two outer bearing journals configured to attach to an inner crankshaft bearing, an unsupported section positioned axially between the inner bearing journal and one of the outer bearing journals, and only three rod journals each configured to attach to a separate piston rod.

Abstract: A compression ring for an engine piston includes an upper and lower face, and an inner face positioned between the upper and lower faces along an inner diameter of the ring. An outer face is positioned between the upper and lower faces along an outer diameter of the ring and is formed by a continuous curve along the axial direction of the ring. The continuous curve has first and second convex surfaces connected by a concave surface with each convex surface defined by first and second radii, respectively. A method of forming a piston compression ring includes machining an outer face of the ring to form a continuous curve along an axial direction of the ring, where the continuous curve has a first convex section and a second convex section connected by an intermediate section.