SKU: 84400020799

Holley Diecast In-Tank RetroFit Fuel Module Returnless System - 12-158

Sale price$382.48 Regular price$424.98
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Ships within 48 hours · Estimated delivery Aug 19 - Aug 24

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Description

Holley Diecast In-Tank RetroFit Fuel Module Returnless System - 12-158Overview: Are you interested in an EFI retrofit kit, but just can't get past the complication of the fuel system? Holley is proud to introduce their Universal In Tank Retrofit Fuel Modules! Available in return and returnless versions, you can rest assured Holley has the solution you need for your EFI fuel pump woes. Now you can convert your factory tank or fuel cell to an in tank EFI fuel system quickly and easily! And add the benefits of a Holley

Overview:

Are you interested in an EFI retrofit kit, but just can't get past the complication of the fuel system? Holley is proud to introduce their Universal In-Tank Retrofit Fuel Modules! Available in return and returnless versions, you can rest assured Holley has the solution you need for your EFI fuel pump woes. Now you can convert your factory tank or fuel cell to an in-tank EFI fuel system quickly and easily! And- add the benefits of a Holley Hydramat in the process! The conversion is easily accomplished with basic tools and requires no welding or fabrication. The aluminum module design includes a die cast pump hanger bracket to control pump vibration while also providing a low profile design to fit where space is at a premium. Holley's innovative clamping system and integrated fuel pump makes it easy. Once installed, hook up your fuel lines and your power source/ground and you're off and running! NO hassle! Supports up to 550 EFI or 700 Carb HP (@ 60 PSI at 13.5 Volts / 10.4 AMP Draw) Of course there are many variables, estimates are based on gasoline. Individual systems will vary based on fuel system design, regulator type, fuel cell location, etc...

Features:

  • The easiest way to convert your vehicle to an in-tank, EFI fuel system
  • Installs in any fuel tank from 7” to 12” deep to fit a wide variety of applications
  • The low profile design is only 1.275" thick above the tank mounting surface for added clearance when needed
  • The innovative clamping system allows you to locate the module anywhere in the tank beside your existing sending unit
  • The clamping system allows you to rotate the unit 360 degrees for easier clocking of the plumbing and wiring locations under your ride
  • Includes innovative Holley Hydramat to ensure consistent fuel supply. The 3” x 15” HydraMat mounting flange has 6 clocking pin locations to allow for 360 degree adjustment to clear sending unit levels or any tank floor restrictions that you might encoun
  • Die cast aluminum construction for corrosion resistance and long lasting good looks
  • ¼” NPT ports for a wide variety of plumbing options
  • Ideal for Terminator EFI, Sniper EFI, MSD Atomic EFI or any TBI of EFI conversion
  • Optional roll over valve available
  • Two different fuel pumps are available to match your requirements - 255LPH or 400LPH for both return and returnless style systems

Application:

Year Make Model Submodel Engine Size
Universal

Specs:

Application Universal
Brand Holley
Diameter 4.8"
Emission Code 3
Free Flow LPH 255
Material Die Cast Aluminum
NPT Thread 1/4 NPT
Product Type Fuel Pump Module
Warning California Proposition 65
Warranty Limited 90 Day
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 84400020799

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J
Verified Purchase
Jackson Caesar
Whiting, US
★★★★★ 5
Great investment, and easy to assemble.
Color: Grey
Excellent dividers for the home. I purchased this set 3 years ago and recently had to place another order because the first order proved to be a perfect accessory in my basement apartment. As previously mentioned, I am in a basement apartment, and with these dividers, I can take an open space and create compartments. After a while, you forget that that open space was once a single room. These options added a great deal to my "Fonshuay," and lifestyle. This is a great investment and it was easy to assemble.
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Reviewed in the United States on September 11, 2025
W
Verified Purchase
wlytle
Chelsea, US
★★★★★ 1
NO instructions
Color: Grey
there were no instructions with this and it came in 100's of pieces. NOTHING, no picture, kind of hard to assemble when you dont know where to start
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 11, 2025
C
Verified Purchase
Cristina Moreta
Chelsea, US
★★★★★ 5
Me cubrió exactamente como esperaba
Color: Grey
Cumplió mis expectativas
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 8, 2026
J
Verified Purchase
JV in Idaho
Battle Creek, US
★★★★★ 5
Very nice quality and appearance
Color: Beige
They were surprisingly stout and went together well. We had to return them because when we took them to where they would be used, they were too big to work in that location. Dang. But if we needed them in the future, I wouldn't hesitate to purchase them.
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Reviewed in the United States on October 31, 2025
S
Verified Purchase
shellz
Whiting, US
★★★★★ 3
Poor quality
Color: Grey
Temporary fix, poor quality, get what you pay for.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on November 22, 2025

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