Bypass Valve

• 2004-2008 Subaru | Forester XT
• 2015–2021 Subaru | WRX
• 2004–2021 Subaru | WRX STI
• 2002–2007 Subaru | WRX

Unlock faster turbo response, eliminate boost leaks, and ensure consistent tuning with our fully redesigned wave spring bypass valve for Subaru GD chassis STi, WRX, and Forester XT.

Key Features

• Fully machined monobloc design from 6061-T6 aluminum using advanced 4-axis CNC milling

• Fast-acting piston and wave spring system eliminates slow, diaphragm-based operation

• Holds significantly higher boost pressures without leaking for improved tuning consistency

• Purges charge pressure quickly on throttle lift, reducing compressor surge and enabling quicker turbo spool

• Direct OEM replacement for factory valve with improved reliability and performance

• Clockable CNC-machined banjo fitting for easy install orientation

• Patented internal design with no rubber diaphragm to degrade or leak boost

• Stainless steel hardware for long-lasting durability

• 100% machined and assembled in-house in Woodland, WA

Function Overview

• Evacuates boost pressure from the charge circuit when the throttle closes to prevent compressor surge

• Dumps pressure downstream of the MAF sensor, maintaining accurate air measurements and preventing afterfire or overly rich conditions

• Faster valve response and greater flow capacity compared to factory diaphragm valves, which often leak or open slowly

• Ideal for both stock and pro-tuned vehicles; re-tune recommended only if replacing a leaking factory valve to adjust for sealed boost

Fitment

• Subaru STI 2002–2021 (GD, GR, GV, VA chassis)

• Subaru WRX 2002–2007 (GD chassis)

• Subaru Forester XT 2002–2007 (SG chassis)

Installation & Notes

• Direct bolt-on replacement, installs using existing hardware

• Consult your tuner if upgrading from a leaking valve to avoid unintended boost increases

• Compact, integrated design ensures easy fitment without modifications

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