A piston for an internal combustion engine is disclosed. A bowl-shaped recess is constructed in the combustion face of the piston. The recess has a w-shaped cross-section. The w-shaped cross-section is unsymmetrical and has at least one side that is mostly vertical. The recess is positioned off-center in the face of the piston so that fuel that is injected into the cylinder is redirected by the recess toward a center space of the cylinder thereby improving combustion of fuel in the cylinder and preventing fuel from accumulating about a periphery of the combustion chamber.