Overview Holley Billet Fuel Pressure Regulators are part of a complete line of fuel system products from Holley. They are precision machined from 6061-T6 billet aluminum for strength and durability. These regulators are adjustable from 4-65 psi and will handle both carbureted and EFI applications. A second pressure spring is included allowing you to increase the fuel pressure range up to 65 psi for EFI systems. They are offered with two port sizes, 3/8" NPT or 6AN to adapt to your new or existing fuel lines. So, if you are currently running a carbureted system but plan to upgrade to EFI in the future, these regulators will have you covered either way. Adjustable billet by-pass return style fuel pressure regulator 3/8" NPT Boost Reference - 1:1 Features Adjustable from 4-65 psi for precise fuel pressure adjustments Constructed of billet aluminum with a black anodized base and a clear anodized top for good looks Used in systems with a return line back to the tank (1) 3/8” NPT Inlet; (1) 3/8” NPT Outlet; and (1) 3/8” NPT Return Port Includes fitting for manifold reference Includes an 1/8 NPT gauge port Boost Reference - 1:1 The 4-15 psi carbureted spring comes installed in the regulator Compatible with diesel fuel and E85
