Holley 12-803 Fuel Pressure Regulator 2 ports 4.5-9 Psi Adjustable

Holley 12-803 Fuel Pressure Regulator is designed to precisely control the fuel pressure from the pump to the carburetor, helping your engine perform consistently across idle and driving conditions. With an adjustable range from 4-1/2 to 9 psi, you can dial in the exact fuel delivery your mix requires for optimal throttle response and smooth operation.

Key features that set it apart

• Adjustable fuel regulation from 4.5 to 9 psi for precise tuning
• Restriction:.220" (7/32") orifice for consistent flow characteristics
• Ports: 3/8" NPT with 1 inlet and 2 outlets, offering flexible routing for single or dual-carb setups
• Chrome finish for a durable, corrosion-resistant appearance
• Mounting bracket included for straightforward installation
• Factory pre-set at the service point, eliminating guesswork during first install

Why control fuel pressure?

Too much fuel pressure can overwhelm a needle and seat, leading to flooding and drivability issues. This regulator ensures the right pressure reaches the carburetor, supporting crisp throttle response, stable idle, and reliable performance across a range of operating conditions.

Versatility and installation

The 1 inlet and 2 outlets provide flexible routing—perfect for feeding a single carburetor or branching to multiple lines for dual-carb configurations. With a chrome finish and a mounting bracket included, it’s designed to integrate cleanly into classic and modern carbureted systems alike.

What you get

Holley 12-803 Fuel Pressure Regulator with a mounting bracket included, ready to install, pre-set at the factory for immediate, accurate setup out of the box.