 Volkswagen air-cooled engine

The Volkswagen air-cooled engine is an air-cooled boxer engine with four horizontally opposed cast-iron cylinders, cast aluminum alloy cylinder heads and pistons, magnesium-alloy crankcase, and forged steel crankshaft and connecting rods.Variations of the engine were produced by Volkswagen plants worldwide from 1936 until 2006 for use in Volkswagen's own vehicles, notably the Type 1 (Beetle), Type 2 (bus, transporter), Type 3, and Type 4.