Radium Engineering FPR-D Fuel Pressure Regulator-Damper – Universal

The Radium Engineering FPR-D is a high-performance fuel pressure regulator and pulse damper integrated into a single compact unit. Engineered for high-flow return-style fuel systems, it consolidates two critical functions—pressure regulation and fuel pulsation control—making it ideal for modern EFI applications. This regulator is not compatible with the low-pressure side of mechanical fuel pumps, including direct injection systems.

Key Features:

• Integrated 1:1 fuel pressure regulator and pulse damper
• Tool-less pressure adjustment with tactile detents (1 psi per click)
• 360° swivelling vacuum reference port with multiple fitting options
• Large 10AN ORB inlet and outlet ports with included 6AN and 8AN adapters
• Auxiliary 1/8" NPT port for gauge or sensor integration
• High pressure stability via stainless steel return orifice
• Fully compatible with petrol, E85, methanol, and other fuels

Mounting & Orientation:

• Two M6x1.0mm threaded mounting holes on body
• Includes anodised aluminium mounting bracket with M6 countersunk bolts and nuts
• Can be mounted in any orientation, including upside down

Fuel Pulse Damping:

• Built-in pulse damper stabilises pressure fluctuations from injectors, pumps, and regulators
• Effective damping range: 40–105 psi (2.8–7.2 bar base static pressure)
• Vacuum reference required for dynamic pressures outside this range

Vacuum Reference Options (Included):

• 3/16" barbed fitting – suits 5/32", 3/16", or 7/32" vacuum hose
• 3AN male fitting – for braided vacuum line integration
• Push-to-connect fitting – compatible with 1/4" hard plastic tubing
• Vacuum plug – for returnless, non-referenced systems

Fuel Compatibility:

• Unleaded, leaded, oxygenated fuels
• Alcohol blends – methanol, ethanol, and E85

Included Components:

• FPR-D main rotating regulator/damper assembly
• Mounting bracket with M6 hardware
• (2) Barbed vacuum fittings
• (2) 3AN male vacuum fittings
• (2) Push-to-connect vacuum fittings
• (2) Vacuum plugs for returnless configuration
• (2) 6AN male adapters
• (2) 8AN male adapters
• 1/8" NPT port plug
• 5/32" vacuum hose and Y-adapter

Fuel Pressure Range:

• Minimum: 18.5 psi (1.3 bar)
• Maximum: Dependent on fuel pump relief valve or ECU current limit

Important Notes:

• This regulator must be installed after the fuel rail in a return-style system
• Not suitable for dead-head systems (see Radium MPR for dead-head configurations)
• Do not use on low-pressure side of mechanical fuel pumps or DI systems