Holley Carbureted Fuel Pressure Regulator + Block w/ 0-15 PSI Pressure Gauge. BRAND NEW IN BOX. Holley Chrome Carbureted Fuel Pressure Regulator # 12-804. Gasket Fuel Block w/ 0-15 PSI Liquid Filled Gauge # 1564. Holley fuel pressure regulators are designed to precisely control the fuel pressure from the fuel pump to the carburetor. Too much fuel pressure for a given needle and seat assembly can overload the needle and seat and may cause flooding or drivability problems. Each Holley fuel pressure regulator is fully adjustable so regulating the fuel pressure to your engines needs is a simple task. All Holley regulators are pre-set at the factory at 2.8 PSI so there is no guesswork when first installing the regulator. The Holley 12-804 fuel pressure regulator features 3/8 NPT in/out ports. The inlet pressure limitation is 7 psi. Adjustable fuel regulation from 1 to 4 psi. 3/8 NPT ports (1 in, 2 out). Pre-set at 2.8 PSI. Emission Code : 3 /. Inlet Size : 3/8 inch NPT. Outlet Size : 3/8 inch NPT. Pressure Range : 1-4 PSI. Product Type : Fuel Pressure Regulator. Allows you to easily install a fuel pressure gauge in-line almost anywhere. This gold anodized aluminum fuel block has 3/8 inch hose barb on inlet and outlet. It comes complete with a 1-1/2 inch diameter gauge with 1/2 psi increments and a range of 0-15 psi Liquid-filled gauge to resist vibration. Fits 3/8 Fuel Hose. Includes Gauge, Adapter & Clamps. Adapter NPT Size (A) : 1/8 NPT MALE. Gauge Background Color : White. Gauge Bezel : Color Silver. Gauge Range : Up to 15 PSI. Gauge Type : Fuel Pressure. Gauge Writing Color : Black. Male Thread : 1/8 NPT. Pressure Range : 0-15 PSI. Product Type : Fuel Pressure Gauge. Style : Liquid Filled Analog. CP Cometic ACL Ferrea and ARP Kits. Custom Made Package Deals. Head and Main Studs. Your address must be confirmed. Buyers who pay with unconfirmed addresses will not be accepted. We always look to satisfy our customers in whatever needs they may have.