Mitsubishi 4A3 engine

The Mitsubishi 4A3 is a family of alloy-headed inline four-cylinder engines introduced in 1993 in the sixth generation of the Mitsubishi Minica kei car. It shares a 72 mm bore pitch with the three-cylinder 3G8 series but has a much shorter stroke, so as to stay beneath the 660 cc limit of the kei class. The 4A30 displaces 659 cc and was offered with a turbocharged 20-valve version, and a lean-burn variant using the Vertical Vortex system arrived on the second generation Pajero Mini in October 1998. A longer-stroke 1.1 litre 4A31 followed in 1997, including a gasoline direct injection version, and was fitted to the Pajero Junior and to the Pistachio, a limited production car.