Fuelab 56504 is a high-performance EFI fuel pressure regulator developed for high-output EFI fuel systems where maximum flow capacity and precise pressure control are essential. The regulator is ideal for motorsport, drag racing, circuit racing, and other high-performance applications using large electric or belt-driven fuel pumps. The extra-large bypass design with a 1/2" return orifice and AN10 ORB ports enables the regulator to handle extremely high fuel flow rates without compromising pressure stability.
The large 1.75" diaphragm ensures fast and stable fuel pressure control at idle, part throttle, and full load. The integrated 1:1 vacuum/boost reference allows fuel pressure to track manifold pressure, maintaining a constant pressure differential across the fuel injectors. The fine-thread adjustment screw provides exceptionally precise fuel pressure adjustment, making it ideal for professional engine tuning and motorsport applications.
The regulator body is CNC-machined from billet aluminium and anodised for excellent corrosion resistance and long service life. Fuelab 56504 is compatible with gasoline, E85, ethanol, methanol, and diesel. It is supplied with a mounting bracket, stainless steel mounting hardware, a 1/8" NPT port for a fuel pressure gauge or sensor, and a 1/8" NPT vacuum/boost port with hose fitting.
Specifications:
Type: Adjustable EFI fuel pressure regulator
Material: CNC-machined billet aluminium
Finish: Black anodised
Fuel type: Gasoline, diesel, E85, ethanol and methanol
Adjustable pressure: 40–80 PSI (approximately 2.8–5.5 bar)
Inlets: 2 x AN10 ORB
Return port: 1 x AN10 ORB
Diaphragm: 1.75" high-flow diaphragm
Return orifice: 1/2"
Gauge port: 1/8" NPT
Vacuum port: 1/8" NPT
Vacuum/boost reference: 1:1
Mounting: Stainless steel mounting bracket included
