A design for a piston engine, cylinder block, and piston is provided. The cylinder block includes a cylinder wall defining at least one cylinder bore for receiving the piston disposed therein. A combustion chamber disposed within the cylinder bore is defined by the piston and the cylinder wall. The combustion chamber has a non-circular cross-section and the cylinder wall includes a first pair of opposing faces and a second pair of opposing faces that converge at rounded intersections. A pair of opposing fuel injectors extend through the cylinder block to the cylinder bore. The pair of opposing fuel injectors are positioned along the second pair of opposing faces of the cylinder wall such that the pair of opposing fuel injectors spray converging fuel plumes into the combustion chamber to reduce air/fuel stratification across the non-circular cross-section of the combustion chamber.