The Subaru EJ207 engine found in the JDM Impreza WRX STi features an 8:1 compression ratio and is a member of the EJ20 series. These were introduced in 1989, intended as successors to the earlier Subaru EA engines. The EJ series is the mainstay of Subaru's engine lineup, and all engines in this series are 16-valve flat-four horizontal configurations, available with a double overhead camshaft (DOHC) arrangement. These engines are often used for engine swaps in light aircraft, kit cars, and air-cooled Volkswagens, and are also a popular swap for the Volkswagen Type 2 equipped with the Wasserboxer engine. The lead engineering for the EJ series was provided by Masayuki Kodama, Takemasa Yamada, and Shuji Sawafuji of Subaru's parent company, Fuji Heavy Industries. The EJ207 features a semi-closed deck block.
Plug and play application. Short duration suitable for street manners, with a slight lope at idle. Excellent all-around spec. Stock springs OK.