GFB Spares- Atmosphere Conversion Kit suits T9103 & T9133

🔧 GFB Spares- Atmosphere Conversion Kit (T9103 / T9133 Compatible)

THE SIMPLE UPGRADE FOR FULL ATMOSPHERE SOUND

Convert your Mach 2 or compatible GFB diverter valve from recirculating (plumb-back) to full atmosphere venting for maximum blow-off sound, while maintaining reliable operation.

⚙️ GFB Spares- Atmosphere Conversion Kit KEY FEATURES

• Direct conversion kit for GFB Mach 2 (T9103 & T9133)
• Enables full vent-to-atmosphere operation
• Includes all required components for conversion
• Designed to maintain stable idle and prevent stalling
• Retains OEM drivability when correctly installed
• Made for easy bolt-on configuration changes

🧩 WHAT’S INCLUDED

• Atmosphere vent trumpet (for increased sound)
• Firmer control spring (for correct valve behaviour under vacuum/boost)
• 33mm recirc hose block-off plug

🔊 FUNCTION OVERVIEW

This kit modifies the Mach 2 setup so that:

• The piston remains closed at idle
• Boost air is released externally instead of recirculated
• Sound output is significantly increased under throttle lift

👉 Result: louder turbo “whoosh” without losing proper valve control

🔬 TECHNICAL INSIGHT

To safely run atmosphere venting, the system must:

• Maintain stable idle vacuum sealing
• Prevent valve float under low-load conditions
• Ensure correct spring preload for engine vacuum characteristics

The firmer spring included helps prevent:

• Idle instability
• Compressor surge
• Stalling or rich running issues

🔩 SPECIFICATIONS

• Product Type: Atmosphere conversion kit (BOV accessory)
• Compatible Systems: GFB Mach 2 (T9103 / T9133)
• Function: Recirc → Atmosphere conversion
• Components: Trumpet + spring + hose plug
• Installation: Bolt-on upgrade (no machining required)

🚗 VEHICLE APPLICATIONS

SUBARU platforms including:

• WRX MY01–02 (Bugeye)
• WRX MY03–05 (Peanut Eye)
• WRX MY06–07 (Hawkeye)
• STi MY03–07
• STi MY08–13
• XT Forester MY05–08 (Series II)

🏁 PERFECT FOR

• Drivers wanting louder turbo sound
• WRX / STi street builds
• Owners upgrading from silent recirc setups
• Plug-and-play sound + performance customisation