Description

MACH 2 ATMOSPHERE UPGRADE KIT TO CONVERT FROM RECIRCULATING TO ATMOSPHERE VENTING.

Includes trumpet, firmer spring, and 25mm hose plug.

To vent the Mach 2 to atmosphere, you need to ensure the piston stays closed at idle, and the recirc hose is plugged. The 5925 Atmosphere Conversion Kit includes a 25mm hose plug to block off the recirc hose, a trumpet to replace the hose outlet on the Mach 2 (not necessary for functionality, but makes the sound louder!), and a firmer spring (part # 6115).

The Mach 2 is supplied with a softer spring (part # 6116) that is suitable for recirculation venting or cars with idle vacuum of 18inHg or less. If the piston stays closed with the existing spring in the Mach 2, there is no need to swap it out. However, if the piston hovers open at idle even with the spring pre-load maxed, the firmer spring in this kit should be installed to prevent stalling or backfiring.

Specifications

Compatibility

  • 1996 - 2005 VW Passat, B5-B5.5 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1995 - 2001 AUDI B5 Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1995 - 2001 AUDI B5
  • 1997 - 2005 VW Golf, GTI Mk4 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1998 - 2006 AUDI TT, 8N 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1998 - 2006 AUDI TT, 8N 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1998 - 2006 AUDI TT, 8N 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2005 - 2009 VW Polo, GTI Mk4F (Typ 9N3) 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1999 - 2003 AUDI S3, 8L Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2008 - 2025 FORD AUSTRALIA, XR6 FG 4.0L turbo
  • 1995 - 2001 AUDI B5 Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1995 - 2001 AUDI B5
  • 1999 - 2025 VW New, Beetle 1st Generation 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2001 - 2005 AUDI B6 Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1999 - 2003 AUDI S3, 8L Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2001 - 2005 AUDI B6 Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1998 - 2006 AUDI TT, 8N 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2002 - 2008 FORD AUSTRALIA, XR6 BA-BF 4.0L turbo
  • 2002 - 2008 FORD AUSTRALIA, XR6 BA-BF 4.0L turbo
  • 2002 MAZDA SP, Turbo
  • 1996 - 2003 AUDI 8L Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2006 - 2011 FORD AUSTRALIA, Territory SY 4.0L turbo Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2014 - 2025 SUBARU XT
  • 1998 - 2006 AUDI TT, 8N 1.8t

MACH 2 ATMOSPHERE UPGRADE KIT TO CONVERT FROM RECIRCULATING TO ATMOSPHERE VENTING.

Includes trumpet, firmer spring, and 25mm hose plug.

To vent the Mach 2 to atmosphere, you need to ensure the piston stays closed at idle, and the recirc hose is plugged. The 5925 Atmosphere Conversion Kit includes a 25mm hose plug to block off the recirc hose, a trumpet to replace the hose outlet on the Mach 2 (not necessary for functionality, but makes the sound louder!), and a firmer spring (part # 6115).

The Mach 2 is supplied with a softer spring (part # 6116) that is suitable for recirculation venting or cars with idle vacuum of 18inHg or less. If the piston stays closed with the existing spring in the Mach 2, there is no need to swap it out. However, if the piston hovers open at idle even with the spring pre-load maxed, the firmer spring in this kit should be installed to prevent stalling or backfiring.

  • 1996 - 2005 VW Passat, B5-B5.5 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1995 - 2001 AUDI B5 Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1995 - 2001 AUDI B5
  • 1997 - 2005 VW Golf, GTI Mk4 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1998 - 2006 AUDI TT, 8N 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1998 - 2006 AUDI TT, 8N 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1998 - 2006 AUDI TT, 8N 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2005 - 2009 VW Polo, GTI Mk4F (Typ 9N3) 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1999 - 2003 AUDI S3, 8L Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2008 - 2025 FORD AUSTRALIA, XR6 FG 4.0L turbo
  • 1995 - 2001 AUDI B5 Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1995 - 2001 AUDI B5
  • 1999 - 2025 VW New, Beetle 1st Generation 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2001 - 2005 AUDI B6 Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1999 - 2003 AUDI S3, 8L Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2001 - 2005 AUDI B6 Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 1998 - 2006 AUDI TT, 8N 1.8t Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2002 - 2008 FORD AUSTRALIA, XR6 BA-BF 4.0L turbo
  • 2002 - 2008 FORD AUSTRALIA, XR6 BA-BF 4.0L turbo
  • 2002 MAZDA SP, Turbo
  • 1996 - 2003 AUDI 8L Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2006 - 2011 FORD AUSTRALIA, Territory SY 4.0L turbo Note: When installing a GFB valve, it must be installed in the OPPOSITE orientation to the factory plastic Bosch valve - i.e. air must enter the GFB valve at the bottom, and dump through the sides.
  • 2014 - 2025 SUBARU XT
  • 1998 - 2006 AUDI TT, 8N 1.8t

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