GFB Mach 2 TMS Recirculating Diverter Valve for Subaru Turbo Models

The GFB Mach 2 TMS Recirculating Diverter Valve is a direct-fit upgrade for selected Subaru turbocharged vehicles, including Legacy GT, WRX, STi, Impreza GT, XT and B4 models from the late 1990s and early 2000s. It replaces the factory bypass valve with a high-performance, reliable recirculating valve that improves boost control and throttle response while keeping induction noise minimal.

Unlike atmospheric blow-off valves, the Mach 2 fully recirculates excess boost pressure back into the intake system. This helps maintain stable airflow, improved drivability and reduced noise, making it ideal for daily-driven cars and performance builds alike.

Faster Boost Recovery with TMS Technology

GFB’s TMS (Turbo Management System) allows the valve to open progressively in response to boost pressure rather than operating in a simple open/close manner. This enhances boost recovery after gear changes, smooths out throttle modulation and delivers a more responsive driving experience.

OEM-Style Quiet Operation

With full recirculation rather than venting to atmosphere, the Mach 2 retains quiet, factory-like performance while holding boost more effectively than many stock bypass valves. This makes it suitable for both OEM and modified turbo setups without unwanted noise.

Built for Reliability

Factory diverter valves can degrade under high boost and elevated intake temperatures. The Mach 2 is designed using robust materials and precision machining to provide improved durability and consistent boost holding over time.

• CNC-machined billet aluminium valve body
• Durable diaphragm and spring assembly
• Carefully calibrated spring rates for stable boost holding
• Quiet OEM-style operation with full recirculation