More ACT parts:All ACT parts WRX 2022+ WRX 2015-2021 WRX 2008-2014 WRX 2002-2007 STI 2008-2014 STI 2004-2007 BRZ 2013-2020 Drivetrain Clutch Drivetrain Clutch Discs / Replacement Parts Drivetrain Flywheels
Shop ACT parts for the 2015-2021 Subaru WRX STI. The VA-chassis STI kept the EJ257 2.5-litre turbocharged flat-four and Driver Controlled Center Differential (DCCD) all-wheel drive - every ACT product in this collection is fitment-tagged for that exact vehicle, so check the product fitment notes against your car before ordering.
Everything in this collection - each product listed here is a ACT part fitment-tagged for the 2015-2021 Subaru WRX STI. Fitment can still vary with trim level and factory options, so confirm the fitment notes on the product page before ordering.
Not interchangeably - the VA STI kept the EJ257 while the WRX moved to the FA20, so STI engine parts are EJ parts, not FA20 WRX parts. Everything in this collection is tagged for the STI specifically; check fitment notes rather than assuming WRX crossover.
The full ACT collection is linked at the top of this page. From there you can also shop ACT by vehicle or by part type - WRX 2022+, WRX 2015-2021, WRX 2008-2014, WRX 2002-2007, STI 2008-2014, STI 2004-2007 and more are all linked above.