High Quality Content by WIKIPEDIA articles! The Subaru EJ engine is a series of four-cycle automotive engines that were manufactured by Subaru. They were introduced in 1989, intended to succeed the previous Subaru EA engine. The EJ series is the mainstay of Subaru`s engine line, with all engines of this series being 16-valve flat-4 horizontal, with configurations available for single-, or double-overhead camshaft arrangements (SOHC or DOHC). Naturally aspirated and turbocharged versions are available, ranging from 96 to 320 horsepower. These engines are commonly used in light aircraft, kit cars and engine swaps into air-cooled Volkswagens, but it`s also popular as a swap into the wasserboxer engined Volkswagen Type 2. Primary engineering on the EJ series was done by Masayuki Kodama, Takemasa Yamada and Shuji Sawafuji of Fuji Heavy Industries, Subaru`s parent company.