SKU: 86359183497

Holley HP EFI ECU and Harness Kits 550-606

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

Ships within 48 hours · Estimated delivery Sep 16 - Sep 21

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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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4.1 ★★★★★
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J
Verified Purchase
J
San Leandro, US
★★★★★ 4
Not invincible but good value
Color: 5pack, Size: Large
Great value for the money. We have 3 dogs and they are pretty strong chewers. They lasted a few months but ultimately succumbed to their inevitable doom. They arrived well packaged and with no unusual odors.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 28, 2026
A
Verified Purchase
Amazon Customer
Draper, US
★★★★★ 5
One of the best indestructible dog toys we've bought
Color: 5pack, Size: Large
So we adopted a pup in December and she tears up everything! I mean, Everything! My CPAP, garden hoses, trucks seat belt and backup camera wiring. Every single dog toy with stuffing, dismantle them in minutes. So many dog toys say they are are tear proof. nope! We have tons of stuffing all over our 5 acres. Hen m wife bought these. Beside the bones she bought, these are the only things she can't seem to destroy and she loves them!!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 3, 2026
S
Verified Purchase
susan said so
Lowell, US
★★★★★ 5
BEST Dog Toys EVER! JRT approved
Color: 5pack, Size: Large
🌟 🌟 🌟 🌟 🌟 for these toys! We have terriers who have NEVER met a toy they couldn't destroy... until now. We've had them over a week an all 5 are still intact, crinkly, and squeakers squeaking - and they're played with constantly! When I tell you I've never, in all my years of JRT ownership and rescue, had a toy last 24 hours, much less a WEEK? Well, lots of you will know how astonishing that is! We've currently got 5 dogs (2 fosters, anyone looking for a project?) so the package size is perfect. Get 'em.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 11, 2026
P
Verified Purchase
Palm Tree Villa
Whiting, US
★★★★★ 5
Great toy, they go the distance!
Color: 5pack, Size: Large, Color: 5pack, Size: Large
Best typy of toys for my pups. Love them. They last!! Chewing tug games. Love them. The squeakiest don’t come out ! Big plus’s. and don’t last long with my dogs, which for me is a big plus’s. Those squeakier drive me crazy!! If they get too yucky, toss them in the washer/dryer! Good to go again.
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Reviewed in the United States on March 29, 2026
J
Verified Purchase
Joan Brown
Grantham, US
★★★★★ 4
String but not indestructible.
Color: 5pack, Size: Large
They’re cute and strong for a dog that likes to bite into toys. Not indestructible.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 13, 2026

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