Fuelab 52501 is a compact, high-performance, adjustable EFI in-line fuel pressure regulator designed for high-performance vehicles, motorsport, and other EFI fuel systems where installation space is limited and precise fuel pressure control is essential. The in-line design makes the regulator ideal for installation directly in the return line without the need for a conventional fuel rail mounting.
The internal bypass design ensures stable fuel pressure during idle, part throttle, and full load. The integrated 1:1 vacuum/boost reference allows fuel pressure to follow manifold pressure, maintaining a constant pressure differential across the fuel injectors. The regulator is compatible with gasoline, diesel, E85, ethanol, and methanol, making it suitable for both street and motorsport applications.
Fuel pressure is continuously adjustable from 25 to 90 PSI (approximately 1.7–6.2 bar). The fine adjustment thread allows precise fuel pressure tuning. The regulator features one AN6 ORB inlet and one AN6 ORB return port in a compact in-line design for simple, space-saving installation.
Fuelab 52501 includes a flexible stainless steel mounting bracket, a 1/8" NPT gauge port with plug, and a 1/8" NPT vacuum/boost port with hose fitting. The anodized billet aluminum construction provides excellent corrosion resistance and long service life under demanding conditions.
Specifications:
Type: Adjustable EFI in-line fuel pressure regulator
Material: CNC-machined billet aluminum
Finish: Anodized
Fuel type: Gasoline, diesel, E85, ethanol, and methanol
Adjustable pressure: 25–90 PSI (approximately 1.7–6.2 bar)
Inlet: 1 x AN6 ORB
Return port: 1 x AN6 ORB
Gauge port: 1/8" NPT
Vacuum port: 1/8" NPT
Vacuum/boost reference: 1:1
Mounting: Stainless steel mounting bracket included
