Perrin - Subaru 15-21 WRX - Air Oil Separator Kit (Wrinkle Black) BF2025 The Stage 1+ Drivetrain Package

The Stage 1+ Drivetrain Package Includes Subaru 6-Speed Front Shifter Bushing

The anodizing keeps the blow off valve looking great during its lifespan

Super low-wear diaphragm spring

which features increased filtration surface area compared to the stock paper filter

and Green Spring Rated -15 InHg (installed)

Perrin - Subaru 15-21 WRX - Air Oil Separator Kit (Wrinkle Black) BF2025 The Stage 1+ Drivetrain PackageOVERVIEW The PERRIN Air Oil Separator traps oil from the crankcase vents before it enters the intake, reduces carbon build up, increases intercooler efficiency, which reduces the chance of performance robbing detonation. NO TUNING REQUIRED Increase horsepower and torque without ECU recalibration or tune! This part is designed and tested to work safely on your vehicle without any tuning required! However, more power can be gained with proper ECU