This ACL High Performance oil pump is built for the Subaru EJ20, EJ22, and EJ25 flat-four engine family, designed as an upgrade over the factory oil pump for improved oiling under performance use.Specifications: Type: Oil Pump Engine Fitment: Subaru EJ20 / EJ22 / EJ25 Part Number: OPSB1478HP FAQWhat engines does this oil pump fit?The Subaru EJ20, EJ22, and EJ25 flat-four engines.Is this a performance upgrade or stock replacement pump?This is ACL's High Performance oil pump, intended as an upgrade over the factory pump.Does this replace the factory oil pump?Yes, it's a direct replacement for the factory oil pump on the listed EJ-series engines.{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"What engines does this oil pump fit?","acceptedAnswer":{"@type":"Answer","text":"The Subaru EJ20, EJ22, and EJ25 flat-four engines."}},{"@type":"Question","name":"Is this a performance upgrade or stock replacement pump?","acceptedAnswer":{"@type":"Answer","text":"This is ACL's High Performance oil pump, intended as an upgrade over the factory pump."}},{"@type":"Question","name":"Does this replace the factory oil pump?","acceptedAnswer":{"@type":"Answer","text":"Yes, it's a direct replacement for the factory oil pump on the listed EJ-series engines."}}]}