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 Jul 30 - Aug 4

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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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4.0 ★★★★★
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Verified Purchase
Ctg1363
Bozeman, US
★★★★★ 5
My tea stays warm to the bottom of the cup!!!
I am so glad I purchased this mug water. I drink tea all day but it cools down quickly. Since I purchased this mug warmer my tea stays hot to the bottom of the cup. The temperature is adjustable so you can keep your drink at your desired temperature. The top is glass and wipes clean easily. I like the rubber gasket that fits on top of the warmer. It keeps your mug in the center of the warmer and should you have a spill it catches the liquid. I've been using it every day for over a month now and it's going strong and is reliable. Perfect for personal use or as a gift.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 2, 2026
S
Verified Purchase
Sarah Akin
Cuba, US
★★★★★ 5
Keeps my coffee as hot as I want it to be
Color: Silver
This coffee warmer is much better than the candle warmer that I was using for my coffee before. With a range of 3 temperatures, I have a choice of temperatures from hot to very, very hot, and the warmer shuts itself off after a while, just in case I forget. The description advises that ceramic cups do not retain heat as well as flat-bottomed cups, but I have not found that to be a problem. Coffee in my ceramic mug stays as hot as I want it to be. The knob on the side makes this warmer easy to turn on and to select a temperature, plus I feel that it is a good value.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 11, 2026
C
Verified Purchase
Cecilia Tosh
West Palm Beach, US
★★★★★ 5
Perfect Mug Warmer
Color: Black
I bought this to replace one I'd had for more than 25 years & I'm glad I got this one. Keeps my hot drinks hot for hours & will shut off after that. Quickly heats back up when needed. Very sleek looking. Easy to set up. Just take it out of the box & plug it in.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 12, 2026
A
Verified Purchase
Amazon Customer
Omaha, US
★★★★★ 5
I love it for my workspace! Hot tea all day
Color: Wood Grain
I love this item. The size is perfect, as I prefer something less bulky for my work desktop. It isn't as fancy as others that has the digital display screen, which is fine by me, because I don't necessarily need that. The knob and different colors that indicate the temperature range works fine. The temperature on this thing works fantastically well for me. Using it on the lowest setting keeps my drink nice and hot in a cold office. I use a heatproof glass teapot with this and its a good fit. It keeps my tea hot throughout the day, so I am able to pour smaller amounts of drink and take my time sipping it throughout the day without worrying that it will get cold. At point I almost forgot that it has an automatic shut-off safety feature when I noticed it was off. So that is a good feature to have. I highly recommend this.
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Reviewed in the United States on January 15, 2026
M
Verified Purchase
MB
Lowell, US
★★★★★ 4
Requires a very specific mug to be useful.
Color: Black
The hotplate itself gets hot enough on its highest setting where it would burn your finger if you left it one there for more then a couple seconds. However when it come to what mug you can use to transfer that heat to your drink, this WILL NOT work with just any old ceramic, metal or glass mugs. You absolutely need to have a perfectly flat bottom on it. If the center of the bottom of the mug does not make direct contact with the very center of the warmer, it will not transfer heat. So straight way plan of spending another $15 to $20. Amazon has some available with good reviews all be it not a very big selection. I'm giving this 4 stars because the description needs to be very clear about this and its not.
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Reviewed in the United States on May 8, 2026

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