GFB Go Fast Bits 8166 FX-Series EFI Fuel Pressure Regulator

The Go Fast Bits (GFB) 8166 is part of the acclaimed GFB FX-Series of EFI Fuel Pressure Regulators — engineered and manufactured in Australia to deliver precision fuel management for performance and modified vehicles. Compact in form but serious in capability, the FX-Series regulators are designed to support high-horsepower builds running pump gasoline, Ethanol, Methanol, or Diesel fuels.

Key Features:

• 1:1 fuel pressure rise rate for accurate boost-referenced fuel pressure control
• Double-layer, double-reinforced diaphragm with a burst strength exceeding 1000 psi for long-term durability and reliability
• Teflon co-polymer seat with spherical stainless steel valve — retains fuel pressure longer after engine shutdown for consistent, reliable restarts
• O-ring sealed spring preload adjustment screw — eliminates vacuum/boost leakage through the adjustment port
• Static pressure adjustable from 28 psi to 72 psi (2–5 BAR)
• Multiple body ports accommodate a wide variety of fuel system configurations including dual fuel rails, mechanical gauges, and ECU pressure sensors
• Completely serviceable design for long-term performance
• Compatible with Unleaded, Ethanol, Methanol, and Diesel fuels
• Manufactured in Australia in accordance with ISO 9001 quality standards

Unlike conventional aftermarket regulators that rely on a metal-to-metal valve seat — which can bleed down after shutdown — the GFB FX-Series uses a softer, more compliant Teflon seat that positively seals every time, giving factory-like starting behavior even in high-pressure performance applications. The o-ring sealed spring hat further ensures that boost or vacuum signals cannot escape through the adjuster, maintaining accurate fuel pressure control under all operating conditions.