Subaru FA engine

The Subaru FA engine is a gasoline boxer-4 used in Subaru and Toyota cars, developed from the FB engine with weight reduction and durability as its main goals. Although the two families share a common platform, the FA shares very little in dedicated parts with the FB, having a different block, head, connecting rods and pistons. It was developed for the Subaru BRZ, and the first FA engine, the FA20D, was designed to sit as low as possible to reduce the polar moment of the chassis. The FA20 is perfectly square at 86 mm bore and stroke for 1,998 cc, echoing the Toyota AE86. The FA20D uses Toyota D-4S direct and port injection, while the FA20F adds Subaru direct injection and a twin-scroll turbocharger and went into the Legacy, Forester, Levorg and WRX. The 2.4 litre FA24 followed, as the turbocharged FA24F and the naturally aspirated FA24D of the second-generation BRZ and Toyota GR86.