Subaru's EJ251 and EJ252 were horizontallyopposed (or 'boxer') fourcylinder petrol engines. For Australia, the EJ251 engine was first introduced in the Subaru BE/BH Liberty in 1998 and subsequently offered in the BH Outback, GD/GG Impreza RS and Subaru SG Forester. For the Subaru BL/BP Liberty and BP Outback, the EJ251 was replaced by the EJ252 engine.