Fuelab 55501 Fuel Pressure Regulator - Manual (Page 2)

105020521-1, Rev A Sheet 2 of 4
Fuel Straining Filter Required, Typical
Micron Rating: 75-150, Fuelab
75 Micron Filter Recommended. Straining
Filter may be Installed in Fuel Pump,
Consult Pump Manufacturer's Specifications.
to Maximum Pump Flow Rate.
Consult Pump Manufacturer's
Specifications and Recommendations.
Vented Fuel Cell or Fuel Tank.
Tank must be Plumbed According
Follow Fuel Cell Manufacturer's
Recommendations for Proper
Cell Vent Plumbing
Fuel Filter with 60 Micron or
Lower Particle Rating is Required.
Fuelab Filter with 6, 10 or 40
Micron Rating is Recommended.
Fuel Pump,
Fuelab Prodigy 40402 Series
Fuel Pump Recommended.
55501-c Regulator
Typical Dual Inlet
Carburetor Shown
Plumbing Planning Notes:
Minimize plumbing restrictions between carburetor(s) and regulator for peak performance. Use –6AN (3/8”) to
–10AN (5/8”) line as required per flow rate requirements of the vehicle’s engine and fuel pump. See company web-
site for nitrous oxide use and alternate plumbing schematics. See diagram on next page as well as diagram below,
to identify the ports used on the regulator. Pressure is regulated by the regulator to the rest of the fuel system (from
outlet ports), by restricting flow through the inlet port. Plumb the Pressure Reference Port using a fitting (Not
Supplied) for “blow-through” carbureted applications only, “blow-through” means that a turbo or supercharger is
used to pressurize the carburetor(s). When this occurs, fuel pressure must be compensated by the change in float
bowl pressure. If motor is naturally aspirated (Normal carbureted application, with float bowl vented to atmosphere)
allow this port to vent to atmosphere, do not plug or plumb to any pressure source. Use of supplied port filter is
shown below. The fuel line used must handle high pressure. The use of fuel line such as stainless steel braided
line and “AN” style fitting connections is recommended. The fuel ports (one –8AN Inlet Port and two –8AN Outlet
Ports) use “AN” or “military” style fittings. This plumbing standard is commonly used with racing and high
performance applications. See step 6 on next page for additional information on this port standard. A fuel filter with
a 40 micron or lower particle rating is required to be used upstream of regulator and downstream from fuel pump to
protect it and the carburetor from foreign object damage. Reference the Schematic Diagram below for filter
locations. Use of a liquid filled gauge exposed to engine compartment heat is not recommended as the liquid inside
the gauge may exert measurement errors. DO NOT plumb gauge port to any gauge mounted inside the vehicle or
in passenger compartment. A line burst can spill fuel inside passenger compartment and on occupants, possibly
causing serious injury or death. An electric gauge or pressure transducer system is recommended for readings in a
passenger compartment.
Typical Carbureted Fuel System Schematic Diagram:
Installation Steps:
1. Disconnect the ground terminal from battery and allow the vehicle’s engine and exhaust system to cool.
Relieve fuel system per applicable service manual. Follow all Warnings and Cautions written on previous page
of these instructions.
2. Modify, remove or replace other fuel system components as required per established build plan (reference
notes on previous page and above).
3. Use the supplied bracket as a drilling template to mark holes for mounting bracket. Choose a location that
minimizes exposure to excessive heat, near carburetor(s). Mounting bracket can be modified as required.