Plumbing Planning Notes:
Fuel Pump is recommended for external use only. Inlet Straining Filter may be omitted if fuel system is cleaned,
and only pre-strained fuel is used to fill the fuel tank or fuel cell with great care ensuring debris not to enter tank.
Adequate structural mounting and support is the responsibility of the fabricator and installer. Mount the fuel pump
as low as possible without it being vulnerable to road hazards or debris. Minimize the length of the fuel line feeding
fuel pump. Do not use “cross drilled” style 90° elbow fittings, check valves or other restrictions (other than high flow
fuel filter strainer or shut-off valve) before or upstream of fuel pump. Minimize plumbing restrictions between fuel
tank and fuel pump and regulator for peak performance, use -12AN (3/4”) or -16AN (1”). Typically -10AN (1/2”) to -
12AN (3/4”) line is required for the rest of the fuel system, after or upstream of fuel pump. Use of a strainer filter
upstream of fuel pump to reduce risk from foreign object damage (**Special Note: Use only Fuelab 868xx Filter with
100-Micron Rated Filter Element for -12AN Line) is recommended. All fuel line used must handle high pressure.
The use of fuel line such as stainless-steel braided line and “AN” style fitting connections are recommended. The
fuel ports (one -12AN Inlet Port and one -10AN Outlet Port) use “AN” or “military” style fittings. This plumbing
standard is commonly used with racing and high-performance applications. See Step 4 on Sheet 4, for additional
information on this port standard. A fuel filter with a 60 micron or lower particle rating is required to be used
upstream of regulator and downstream from fuel pump to protect it and the fuel injectors from foreign object
damage. Reference the Schematic Diagram below for filter locations. Fuel tank must have a modification of an
additional sump or use aftermarket fuel cell as indicated. Use of a “pick-up” tube system is not recommended. Use
of a liquid filled gauge exposed to engine compartment heat is not recommended as the liquid inside the gauge may
exert measurement errors, all mechanical gauges and pressure transducers have amounts of error due to
temperature fluctuation, be aware of inaccurate pressure readings. 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 electronic gauge or pressure transducer system is
recommended for readings in a passenger compartment.
Do not "Dead Head" Fuel Pump.
Special Note: Use in carbureted systems require a bypass return or relief valve.
Typical EFI V-8 Fuel System Plumbing Schematic Diagram:
110021026-1, Rev A Sheet 2 of 6
40501 Fuel Pump
Fuel Filter with 60 Micron or
Lower Particle Rating is Required.
Fuelab 868xx Series Filter with 6
or 40 Micron Rating is Recommended.
Add high flow check valve to maintain
fuel pressure after pump shut-off if
desired.
-12AN or 3/4" Miniumum
Line Size Required to feed Straining
Fuel Filter and Fuel Pump.
Vented Fuel Cell or Fuel Tank.
Tank must be Plumbed According
to Maximum Pump Flow Rate.
Follow Fuel Cell Manufacturer's
Recommendations for Proper
Cell Vent Plumbing
(2X) Fuel Rails
with Injectors
Y-Block or "T" Fitting,
to Split Flow into Two
Fuel Rail System
Fuel Straining Filter Required, Typical
Micron Rating: 100-150, Fuelab 868xx Series,
100 Micron Filter Recommended.
Fuelab 565xx Series
EFI Regulator
Recomended.
Fuel Gauge Shown in
Gauge Port, Liquid Filled
Gauge may have Error Due
to Temperature Variations.
To Engine Intake Manifold (Air)
