SKU: 86359183497

Holley HP EFI ECU and Harness Kits 550-606

Sale price$1237.47 Regular price$1374.97
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  • USA
  • CAN

Ships within 48 hours · Estimated delivery Sep 19 - Sep 24

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Description

Holley HP EFI ECU and Harness Kits 550-606FORD MPFI HP ECU AND HARNESS KIT 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

FORD MPFI HP ECU AND HARNESS KIT

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 for Water/Meth tu

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 550-606
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: 86359183497

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4.4 ★★★★★
Based on 6 reviews
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Verified Purchase
Judy P.
Natrona Heights, US
★★★★★ 4
My dog is a very aggressive chewer.
Color: Blue
My dog is an aggressive chewer and this lasted about 3 weeks before he started to get into the plastic and I had to throw away. It lasted longer than other chew toys so it was good. However the tail makes it easier for him to chew off into pieces. He gets nervous and needs to chew on something. I find the hard cheese sticks a better option for his nervousness.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 25, 2026
A
Verified Purchase
Amazon Customer
Port Orchard, US
★★★★★ 5
Happy hound!
Color: Yellow, Color: Yellow
My 2 yr old bloodhound destroys every toy in minutes, but not this one. My husband and I actually buy toys to see how long they last for fun. Although the croc is NOT indestructible, it lasts a whole lot longer than most. After an hr or so, I took away the only piece he's chewed off which is part of the back leg. Otherwise nothing else is missing off the croc. Our boy has been very occupied with this new toy and we're satisfied with his new distraction!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 29, 2026
B
Verified Purchase
Baily Gravunder
Lowell, US
★★★★★ 5
Definitely a tough toy
Color: Blue
This is one of the few toys my Boxer/american bulldog mix hasn’t been able to tear apart. He loves chewing on it and I love that he doesn’t chew on stuff he shouldn’t. I have such an issue with toys being torn apart the day I bring them home. I wish there was a safe way for it to have a squeaker since he loves squeakers but I don’t think that is possible.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026
H
Verified Purchase
Hannah
Whiting, US
★★★★★ 5
Croc-sational
Color: Blue
My tough chewer is OBSESSED with Croc. Stands up well, small particles occasionally come off but this beats going thru 3 stuffies in an hour. Good value, easy to clean and great for our 91lb pitty
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026
B
Verified Purchase
barb belshe
Phoenix, US
★★★★★ 5
Withstands very aggressive chewing
Color: Blue
We have a very active and aggressive chewer. Items identified for aggressive chewers are “Gone in 60 Seconds”. This toy is amazing. It has withstood Jake’s many attempts to destroy it and is one of his favorites! It is not hard like acrylic but is hard rubber with some give decreasing risk of fractured teeth. Best toy yet!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 8, 2026

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