Injection port for internal combustion engine

An internal combustion engine having a cylinder with a piston movement area; a piston movably mounted in the cylinder; an ignition system connected to the cylinder; and a fuel delivery system connected to the cylinder. The fuel delivery system has a combined fuel and air injection port extending into the cylinder. The injection port has an end at the piston movement area with a top surface and a different shaped bottom. The bottom surface has an inwardly tapering shape to form a bottom portion of the end of the injection port with a generally semi-conical shape.