Toyota AR engine

The Toyota AR engine family is a series of inline-four piston engines that Toyota first introduced in 2008 for the RAV4 and then used in the Highlander, Venza, Camry and Scion tC. It has a die-cast aluminium engine block and an aluminium DOHC cylinder head, uses timing chains rather than timing belts, and shares much of the technology of the AZ engine that it replaced. It adds variable valve timing on both camshafts, low friction measures such as an offset crankshaft and roller rockers, a three-stage variable oil pump and an acoustic control induction system that switches the length of the intake tract in two stages. The cylinder block is an open-deck, midi-skirt type with cast-in iron liners, and balance shafts are driven from the crankshaft.