SKU: 62968518913

Holley HP EFI ECU and Harness Kits 550-606N

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

Ships within 48 hours · Estimated delivery Aug 8 - Aug 13

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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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Steve
Lowell, US
★★★★★ 4
3.5, Not 3.0
Color: Medium Set of 6
These balls were almost exactly what I needed. I was replacing my boy’s favorite ball, which is the 3” squeaky, spikey ball that fits in the chuck it launcher. Unfortunately I saw the shiny object next to it and because there were SIX balls and a dollar less, I failed to see that these are 3.5” balls instead of 3”…. Great balls but no fitty in the slingy. Buyer beware. No chuck it no problem. Save a buck.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 9, 2026
H
Verified Purchase
HollisHoHo
West Palm Beach, US
★★★★★ 5
MY CHIHUAHUA LOVES THESE BALLS!!
Color: Samll Set of 8
My little chihuahua, BamBam, is addicted to balls, especially little balls that squeak! However, any balls that have material on them, BamBam will tear them apart, swallow the material and then get an upset tummy! These balls saved the day! BamBam LOVES them & she cannot tear them apart! They hold up so well! No matter how much BamBam plays with them, they keep squeaking away!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on July 15, 2025
L
Verified Purchase
Laurens springerslng
New York, US
★★★★★ 5
Great thick squeaky ball
Color: Large Set of 2
These are good thick rubbery squeaky balls. My boy loves them! He's 75lbs. Strong chewer. I hav hard time squeezing to squeak, but he doesn't... He loves it!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 24, 2026
G
Verified Purchase
g a ross
Carnegie, US
★★★★★ 5
Squeaky ball
Color: Large Set of 4
Perfect squeaky ball. Dogs love them. I love that they're durable and their thickness aids their durability. My Great Dane will play alone for hours with a ball.
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Reviewed in the United States on June 20, 2025
R
Verified Purchase
Ricky Bobby
Whiting, US
★★★★★ 5
Fun
Color: Interactive Dog Ball
Fun! Second purchase. Solid and rugged for 22 lb dog. He loves it.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 21, 2025

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