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Holley 12-131
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Holley In-Tank RetroFit Fuel Module


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Holley In-Tank RetroFit Fuel Module $519.95
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In-Tank RetroFit Fuel Module
  • 255 lph Pump
  • Supports up to 550 EFI HP or 700 Carb HP
  • 4.800 in. Diameter
  • 1/4 in. npt Ports
  • Billet Aluminum Module
  • Returnless-Style Fuel System
  • Includes Hydramat
  • Holley 12-131 Details

    255 lph Pumps

    Installation Notes:

    • A 30 amp fuel pump relay and minimum 12 gauge wire are recommended for optimal performance
    • -6 AN lines and fittings are the maximum size recommended for operation due to space limitations between the fuel sending unit and fuel tank


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    Drop-In Retrofit EFI Fuel System

    Are you interested in an EFI retrofit kit, but just can't get past the complexity of the fuel system? Holley's Universal In-Tank Retrofit Fuel Modules take the hassle out of the conversion process. Available in return and returnless versions, you can convert your factory tank or fuel cell to an in-tank EFI fuel system quickly and easily with a retrofit kit  The conversion is easily accomplished with basic tools and requires no welding or metal fabrication. The aluminum module design includes a pump hanger bracket to control pump vibration. An innovative clamping system allows the module to be located anywhere in the tank beside your existing sending unit. A low profile design helps the pump to fit where space is at a minimum in and out of the tank. Once installed, hook up your fuel lines, power source, ground and you're ready to run!


    • The easiest way to convert an older vehicle to an in-tank, EFI fuel system
    • 7 to12 in. adjustable rail allows installation in most stock fuel tanks to fit a wide variety of applications
    • Black anodized aluminum construction for corrosion resistance 
    • 1/4 in. NPT ports 
    • The clamping system allows you to rotate the unit 360 degrees for easier clocking of the plumbing and wiring locations under your ride
    • Ideal for Terminator EFI, Sniper EFI, MSD Atomic EFI or any TBI of EFI conversion
    • Three different fuel pumps are available to match your requirements - 255 LPH, 340 LPH or 450 LPH for both return and returnless style systems
    • 255 LPH Supports up to 550 EFI or 700 Carb hp
    • 340  LPH Supports up to 700 EFI or 900 Carb hp
    • 450 LPH Supports up to 875 EFI or 1100 Carb hp

    Items You Need

    Some parts are not legal for use in California or other states with similar laws / regulations

    Motor Vehicles

    WARNING: Motor vehicles contain fuel, oils and fluids, battery posts, terminals and related accessories which contain lead and lead compounds and other chemicals known to the State of California to cause cancer, birth defects and other reproductive harm. These chemicals are found in vehicles, vehicle parts and accessories, both new and as replacements. When being serviced, these vehicles generate used oil, waste fluids, grease, fumes and particulates, all known to the State of California to cause cancer, birth defects, and reproductive harm.


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    Electrical Cords

    WARNING: The wires of these products contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.