GFB Mach 2 TMS Recirculating Diverter Valve for Subaru Turbo Models

The GFB Mach 2 TMS Recirculating Diverter Valve is a proven upgrade for Subaru turbocharged vehicles, designed to replace factory bypass valves that are prone to boost leaks and inconsistent response. It is commonly fitted to performance Subaru platforms such as the WRX, Forester GT / XT, and Legacy GT.

By fully recirculating excess boost pressure back into the intake system, the Mach 2 maintains stable airflow, factory drivability and smooth throttle response. This makes it ideal for Subaru engines that rely on airflow metering and for drivers who want improved performance without additional noise.

Improved Boost Response with TMS Technology

Factory Subaru bypass valves typically operate in a basic open-or-closed manner, which can lead to slower boost recovery between gear changes and inconsistent throttle response. The Mach 2 addresses these limitations using GFB’s TMS (Turbo Management System).

TMS allows the valve to open progressively in response to boost pressure rather than acting as a simple on/off valve. This results in faster boost recovery after shifts, smoother power delivery during partial throttle inputs and improved drivability in both daily and performance driving.

Quiet OEM-Style Operation

Unlike atmospheric blow-off valves, the Mach 2 fully recirculates vented air back into the intake system. This keeps induction noise to a minimum, prevents hesitation or stalling, and preserves the refined driving characteristics expected from a factory Subaru setup.

Built for Long-Term Reliability

High boost pressures and elevated intake temperatures can quickly degrade factory plastic valves. The Mach 2 is engineered to withstand these conditions using durable materials and precision machining, making it suitable for standard and modified Subaru turbo engines alike.

• CNC-machined billet aluminium valve body
• High-temperature diaphragm construction
• Carefully selected spring rates for consistent boost holding
• Designed for long-term reliability under boost