SKU: 10141508728

HP EFI ECU & Harness Kits - 550-605N

Sale price$1349.97 Regular price$1499.97
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Ships within 48 hours · Estimated delivery Sep 20 - Sep 25

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Description

HP EFI ECU & Harness Kits - 550-605NOverview: Looking for a alternative for your stock or built late model factory FORD EFI engine? How about a replacement ECU for your older Holley C950? Holley has you covered. HP EFI ECU and harness kits are designed to be used with popular factory EFI engines as an alternative to the factory ECU and harness or as a replacement for your C950 ECU. The HP allows you to accurately control the fuel and ignition of your engine along with additional

Overview:

Looking for a alternative for your stock or built late model factory FORD EFI engine? How about a replacement ECU for your older Holley C950? Holley has you covered. HP EFI ECU and harness kits are designed to be used with popular factory EFI engines as an alternative to the factory ECU and harness or as a replacement for your C950 ECU. The HP allows you to accurately control the fuel and ignition of your engine along with additional controls for nitrous, boost or water meth.

Features:

  • Optional 5.7” full-color touchscreen LCD allows easy on-the-fly tuning,data-logging or can be used as an easy to see graphical gauge panel
  • Eight sequentially driven 8:2 peak and hold injector drivers, capable of driving up to 16 low or high impedance injectors as a standard feature. Multiple staged injector strategies
  • Eight channel Distributorless Ignition (DIS)outputs capable of directly driving “Smart” ignition coils or Holley DIS coils. Will drive 2 wire coils with the addition of PN 554-112 high current coil driver module
  • Plug and Play control of factory GM 24x and 58x LSx engines
  • Integrated single channel wide band oxygen sensor control. Works with NTK sensors
  • Internal data-logging standard with a huge 2GB of memory
  • 4 Stage progressive nitrous control
  • Turbo boost control
  • Integrated water/methanol injection control
  • Self-tuning fuel table strategy greatly simplifies tuning process
  • Individual cylinder fuel and spark control allows you to unlock your engine’s potential
  • Works with 4, 6, 8 cylinder engines
  • Unique lb/hr based fueling strategy greatly simplifies and commonizes tuning
  • Advanced idle, closed loop, and enrichment strategies allow for very stable operation
  • ECU is fully potted and can be mounted in the engine compartment or interior
  • Sealed automotive and marine grade connectors
  • Allows for use of common OEM sensors as well as customer sensor calibration input
  • Ignition Plug and Play with GM 24x and 58x LSx engines, GM HEI, Ford TFI, magnetic and hall effect trigger, and other ignition systems. New Plug and Play applications in process. Custom settings can be configured to allow many other applications
  • 1-5 Bar MAP sensor capability
  • Two channel knock control sensor Inputs for both one or two wire knock sensors
  • Dedicated fuel and oil pressure inputs
  • Controls both stepper and PWM Idle Air Control (IAC) motors
  • Speed density, Alpha-N, or combination fueling strategies
  • 4 Programmable high or low Pulse Width Modulated (PWM) outputs and 4 fully configurable inputs can be configured for use
  • 4 Stage nitrous oxide control
  • Fully featured nitrous control eliminates the need for a separate nitrous controller device
  • Can be configured “Wet” or “Dry” with closed loop feedback
  • Progressive control based on time, RPM, or boost, requires part # 554-111
  • Lean or rich safety cutoff
  • Full timing retard/control configurability per stage based on RPM or time
  • Integrated Water/Methanol injection control
  • Uses Holley Water/Meth solenoids specially designed and calibrated for use with this EFI system to allow the user to enter Water/Meth flow as a percentage of fuel injector flow
  • Includes NTK Wideband Oxygen Sensor

Application:

Year Make Model Submodel Engine Size
Universal

Specs:

Brand Holley EFI
Emission Code 3
Ignition Type Coil - (No Timing Control)
Ignition Type Ford TFI
Ignition Type GM HEI Small Cap
Ignition Type Holley Dual Sync Distributor
Injector Connector Jetronic / Minitimer (Bosch)
Product Type EFI System
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: 10141508728

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Reviewed in the United States on February 27, 2026
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Mary
Grantham, US
★★★★★ 3
The colors are way off
Color: 259 ASH BROWN, Size: 1 Count (Pack of 1)
The ash brown is basically black. However, I do think the gel helps set the brow color and I have been using a ash blonde color and then applying the gel.
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Reviewed in the United States on February 9, 2026
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JStewart
Omaha, US
★★★★★ 5
So Good!
Color: 262 BLACK BROWN, Size: 1 Count (Pack of 1)
This is my absolute favorite bow pen I've ever tried. The brush tip is incredibly fine and makes each stroke a perfect hair like finish. I tend to get heavy handed with other options like brow powders so having an option for thin hair like stokes makes it incredibly hard to taken it too far. The tip doesn't dry out to the point of skipping or Inconsistency without you knowing its time to refresh it by capping and shaking, but I do find that it comes back refreshed and even better the more you repeat the capping and shaking step between brows. Easy to hold and design. I wasn't totally blown away with the brow gel it comes with attached to the pen when it comes to hold power. It doesn't flake at all and doesn't leave a cast of white or sheen to the brow, which is a plus. It's just a nice way to loosely set the brow after application. There is some wiggle room with wiping the product off with a q tip if a mistake is made, but once the pigment is dry, it doesn't budge all day, even after intense exercise or humid conditions. I'll be repurchased this like... now, and hope it never gets discontinued!
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Reviewed in the United States on April 10, 2024
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Defective product from Amazon.
Color: 255 SOFT BROWN, Size: 1 Count (Pack of 1)
I have used this product many times and I think it is a good product. I usually buy it at Target. The product I received from Amazon was defective. The pen was totally dried out and I was not able to paint a brow. There was liquid in the brush side, but it is colorless and meant to be a finish to make the color last longer. Maybe just a one time fluke, but I'd purchase this elsewhere.
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