SKU: 62968518913

Holley HP EFI ECU and Harness Kits 550-606N

Sale price$1349.97 Regular price$1499.97
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  • USA
  • CAN

Ships within 48 hours · Estimated delivery Aug 3 - Aug 8

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Description

Holley HP EFI ECU and Harness Kits 550-606NHP ECU AND HARNESS, FORD MPFI, NTK 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

HP ECU AND HARNESS, FORD MPFI, NTK

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 or Bosch 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

  • Universal

Specs

Brand Holley EFI
Emission Code 3
Ignition Type Coil - (No Timing Control)
  Ford TFI
  Holley Dual Sync Distributor
Injector Connector Jetronic / Minitimer (Bosch)
Product Type HP EFI Kit
Part Number 550-606N
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: 62968518913

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Amazon Customer
Boise, US
★★★★★ 5
Great for price
Style: Steam Mop
Works well
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Reviewed in the United States on June 6, 2026
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Kelly M
Louisville, US
★★★★★ 4
Needs a longer cord! But does the job well!
Style: Steam Mop
My only complaint is the cord is not long enough! I have to go around finding every outlet to plug it into to get my whole house clean.
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Reviewed in the United States on May 26, 2026
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p1mkw
Bozeman, US
★★★★★ 3
You get what you pay for
Style: Steam Mop
It's just OK. It does get the job done, but poorly made and I don't expect it to last long. Unlike other steam mops I've had, this one leaves the floor wet. Plus the pad does not pick up any stuck-on gunk that the steam loosened. I had to go back and pick up a few pieces by hand. Instructions say to let the water tank air dry before storing, but the attached lid makes it hard to let air into the tank. In retrospect I should have spent a few dollars more and gotten a better unit.
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Reviewed in the United States on April 22, 2026
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Brandon Winbush
Draper, US
★★★★★ 5
Good purchase for the price point
Style: Steam Mop
This mop is perfect as it is compact while being easy to use. Stuck food on the floor? Not after using this. Crayon? Vanishes. Sticky substance? no more. Great but for the price
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Reviewed in the United States on May 31, 2026
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Candy
Pawtucket, US
★★★★★ 5
It is a keeper for sure!
Style: Steam Mop
This is about 100% better than I ever imagined. It has every feature I want and none of the stuff I don't want. It has a SUPER long cord, it heats up quick and works exactly as it is supposed to. I steam cleaned everything from my stained concrete floors, THE ENTIRE COUCH, and low pile area rugs. Love this thing and SO MUCH cheaper that the competing brands.
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Reviewed in the United States on January 31, 2026

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