page_title: Flat-four engine
section_title: 2000-present
hierarchical_section_title: Flat-four engine / Use in automobiles / 2000-present
caption_attribution_description: Subaru BRZ engine
context_page_description: A flat-four engine, also known as a horizontally opposed-four engine, is a four-cylinder piston engine with two banks of cylinders lying on opposite sides of a common crankshaft. The most common type of flat-four engine is the boxer-four engine, each pair of opposed cylinders moves inwards and outwards at the same time.
  A boxer-four engine has perfect primary and secondary balance, however the two cylinder heads means the design is more expensive to produce than an inline-four engine. Boxer-four engines have been used in cars since 1897, especially by Volkswagen and Subaru. They have also occasionally been used in motorcycles and frequently in aircraft. Cessna and Piper use flat four engines from Lycoming and Continental in the most common civil aircraft in the world - the Cessna 172, and Piper Cherokee.
context_section_description: By the year 2000, most manufacturers had replaced flat-four engines with inline-four engines. A notable exception is Subaru, with the latest iteration of its flat-four engine, the water-cooled Subaru EJ engine being available in turbocharged form in the Subaru WRX sports sedan and its World Rally Car counterpart. Subaru's adoption of all-wheel drive was a factor in retaining the flat-four engine, since the shorter length of this engine assists in fitting the all-wheel drive components into the chassis.  Although it is more expensive than an inline-four engine, the flat-four engine allows Subaru to build an all-wheel drive vehicle at little extra cost from two-wheel drive.
  In 2012, a naturally-aspirated version of the Subaru FA engine was used in the Toyota 86 (also called the 'Subaru BRZ' and 'Scion FR-S') rear-wheel drive sports coupe. This engine is water-cooled, has gasoline direct injection, produces 147 kW (197 hp) and has a displacement of 2.0 L (122 cu in)
  The 2016 Porsche Boxster/Cayman (982) mid-engined sports cars downsized from a naturally aspirated flat-six engine to a turbocharged flat-four engine, Porsche's first flat-four since the mid-1970s. This engine is produced in displacements of 2.0–2.5 L (122–153 cu in) and produces up to 365 hp (272 kW). Several reviewers criticised the Boxster/Cayman for an uninspiring engine sound.
caption: 2012-present Subaru FA water-cooled engine
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