Holley Fuel Pressure Regulator Bypass Billet 3/8” NPT

Regardless of whether you have a carbureted or EFI application, this fuel pressure regulator guarantees precise control (12-879). This Holley bypass regulator is great for systems with a return line back to the tank, whether they use diesel or E85 fuel. It’s pre-installed with a carbureted spring, offering 4-15 in PSI adjustability. However, the second spring extends that range up to 65 for a total scope of 4-65 PSI. Designed with a 1:1 boost reference as well, it’s perfect for performance-driven vehicles. For lasting strength, it bears a 6061-T6 aluminum construction while the black base and clear top are both anodized.

Features and Benefits:
- For systems w/ a return line back to the tank
- Works on carbureted & EFI applications
- Compatible w/ diesel & E85 fuel
- Pre-installed, 4-15 PSI, carbureted spring
- Second spring allows adjustability up to 65 PSI
- Total of 4-65 PSI adjustability
- 1:1 boost reference
- Built from 6061-T6 billet aluminum
- Black anodized base, clear anodized top
- 3/8” NPT inlet, outlet, & return port
- 1/8” NPT gauge port supplied
- Includes fitting for manifold reference

Vehicle Fitment:
- 1965-1985 Ford Mustang
- 1948-1979 Ford F-100
- 1960-1987 Chevy C10