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GFB Mach 2 TMS Recirculating Diverter Valve - Subaru 99-00 WRX/STi/B4 Legacy / 98-04 GT/XT Forester
MPN T9100 · Store SKU gfbT9100
Supplier stock checked 11/7/2026, 5:45:40 AM UTC. Adding a part does not reserve it.
Request a return within 30 calendar days after delivery. New parts must be unopened and unused.
Shipping & returns ↗This policy does not limit rights required by law.Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.
Product details
ALL THE PERFORMANCE WITH OR WITHOUT THE NOISE!, GFB's Mach 2 utilises GFB's proven TMS Technology to ensure rapid boost recovery on gearshift and optimum throttle response, as well as the ability to withstand boost pressures of 100psi+. Put simply, it can hold more boost than any turbo could produce GFB's Mach 2 diverter valve is configured from the factory for full recirculation (i.e. plumb back, diverter, bypass) venting for the performance-minded who just want the benefits without the sound. Atmosphere venting kits also available. The Mach 2 direct fit bolt-on range covers a huge list of popular vehicles. You can also purchase a variety of hose and flange adaptors for custom fitments. Please check the application guide to find the Mach 2 model for YOUR car!, With its single venting outlet, the Mach 2 is configured from the factory for full recirculation (i.e. plumb back, diverter, bypass) venting for the performance-minded who just want the benefits without the sound. Mach II Diverter Valve and atmo option for the performance-minded
Manufacturer fitment & guides
- Subaru WRX/STi MY99-00, B4 Legacy, GT/XT Forester MY98-04
- Manufacturer-supplied application summary from Turn14; this may not be an exhaustive fitment list.
Part-specific notes
- Not CARB approved. Destination and intended-use restrictions must be checked before sale.
- Emissions acknowledgement required before purchase.
- California Proposition 65: Y
