The Subaru FB engine is the third and current generation of gasoline boxer-4 engine used in Subaru automobiles, and was announced on 23 September 2010. It follows the previous generation EJ-series engine which was introduced in 1989 and the first generation EA-series which was introduced in 1966. By increasing piston stroke and decreasing piston bore, Subaru aimed to reduce emissions and improve fuel economy, while increasing and broadening torque output compared to the EJ-series.