GFB Mach 2 atmosphere conversion kit (30 mm blanking plug)

Conversion kit for converting the GFB Mach 2 from recirculation operation to vent-to-atmosphere operation.

The kit includes a sound trumpet, a stiffer spring and a 30 mm hose blanking plug.

To vent the Mach 2 valve to atmosphere, the piston must remain closed at idle and the recirculation hose must be blanked off. The 5930 vent-to-atmosphere conversion kit includes a 30 mm plug to block the recirculation hose, a sound trumpet to replace the hose connection on the Mach 2 valve and a stiffer spring. The sound trumpet is not required for operation, but it produces a louder sound.

The Mach 2 valve is supplied with a softer spring (part number 6116), which is suitable for recirculation operation or for vehicles with 18 inHg or less vacuum at idle. If the piston remains closed with the existing spring in the Mach 2 valve, the spring does not need to be replaced. However, if the piston remains partially open even at the maximum spring preload setting, the stiffer spring from this kit must be installed to prevent the engine from stalling or backfiring through the exhaust system.

The kit is intended for GFB Mach 2 valves with part numbers T9100, T9101, T9102, T9104, T9105 and T9135.