Adjustable Fuel Pressure Range: Regulator can be precisely adjusted from 4.5 to 9 PSI to optimize fuel delivery for carbureted engines and performance applications. Compatible with Holley Fuel Pumps: Designed to work seamlessly with Holley high-performance fuel pumps, ensuring reliable fuel control under demanding conditions. Integrated Gauge Port: Features a 3/8-inch NPT gauge port for convenient fuel pressure monitoring; reducer fitting (Holley 617-6157) required for installation. High-Quality Liquid-Filled Gauge: Includes a stainless steel 0–15 PSI gauge with 1.75-inch face and 1/8-inch NPT connection for accurate, vibration-resistant readings. Complete Fuel Pressure Control Kit: Everything needed to regulate and monitor fuel pressure—ideal for carbureted street, strip, or performance engine setups. Pressure Regulator These adjustable fuel pressure regulators from Holley can be adjusted from 4-1/2 to 9 PSI to regulate fuel pressure for various types of carburetors. Fuel pump regulator works well with Holley high performance fuel pumps. Use one fuel regulator per fuel bowl for high flow applications. This fuel pressure regulator has a 3/8" NPT gauge port and requires reducer 617-6157 to install a fuel pressure gauge. Pressure Gauge High quality, liquid-filled stainless steel fuel pressue gauge for remote mounting. 0-15 psi. 1-3/4" face. 1/8" NPT connection.