SKU: 34360476229

HP EFI ECU & Harness Kits - 550-601N

Sale price$1349.97 Regular price$1499.97
Save 10%

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Jul 13 - Jul 18

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

Description

HP EFI ECU & Harness Kits - 550-601NOverview: Looking for a plug and play alternative for your stock or built late model factory 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

Overview:

Looking for a plug and play alternative for your stock or built late model factory 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:

  • NEW V2 SOFTWARE FEATURES
  • “Quick Start” ignition and fueling strategy for LS x Engines
  • Data Logger. Scalable axes, Smoothing, Multiple graph view ability, Pre-defined notes fields and many more
  • Strip Chart Real-Time Data Viewer
  • Integrated Boost Control - Boost vs Time, Boost vs Gear (Time or RPM), Boost vs RPM, Boost vs Speed, Launch control. Boost launch builder, Over-boost safeties, Boost scramble
  • Traction Control - Power reduction via timing, nitrous percentage or boost (Requires Davis Technologies Holley Module)
  • “Quick Start” fueling for all engines
  • Option for VE based fueling strategy
  • Fuel Map and Learn Function Smoothing
  • Configurable User Password Protection
  • Fully Configurable lap top Gauge Panel
  • 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 tuning precision unmatched in the industry

Application:

Year Make Model Submodel Engine Size
Universal

Specs:

Brand Holley EFI
Emission Code 3
Ignition Type Coil - (No Timing Control)
Ignition Type GM HEI Small Cap
Ignition Type Holley Dual Sync Distributor
Injector Connector Jetronic / Minitimer (Bosch)
Product Type HP EFI Kit
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: 34360476229

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.4 ★★★★★
Based on 487 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
R
Verified Purchase
R.
Whiting, US
★★★★★ 5
Great product
Color: Navy Blue
Awesome product. It does everything I need it to. Very smooth and stylish as well.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 12, 2026
N
Verified Purchase
Nosiest
Pawtucket, US
★★★★★ 4
Cheap and good
Color: Black, Color: Black
I chose the color black and it gives a really nice look, especially with the multicolor led lights around the keys. It is very easy to clean and you can shut off the keyboard to prevent any mess with the iPad. The magnet is very nice and keeps the keyboard in place. The keyboard doesn’t easily slip or anything so it holds the iPad very well. Only bad thing is that over time the iPad begins to scrape off the pain and it leaves your keyboard with some white spots all over :/ but if looks isn’t something that you care about, this is the keyboard for you. Don’t use it for gaming because there is a delay in functionality when you press a key and then try to use the pad. Also, you have to press the keys a bit harder than the usual keyboard. But for the price? This is a great item! Definitely worth my money
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 18, 2026
L
Verified Purchase
Landscapes606
Cuba, US
★★★★★ 5
Works great
Color: Purple
Works just pretty good. My only complaint would be that it can turn on the screen when closed. I put it in my backpack and went throughout my school day only to find out later the battery had drained because the screen would light up and stay on. Did not have this issue with other covers. Easy work around is to just do a complete shutoff or maybe change the settings before putting in away. I just had the habit of keeping mine on because of frequent use in back to back classes.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 8, 2026
T
Verified Purchase
Trinidy Martinez
Draper, US
★★★★★ 5
Great case & keyboard combo
Color: Navy Blue
Great case! Updated my son’s children’s case to this one and he loves it! He feels like it’s a laptop now. The magnetic feature is great & it’s super easy to install!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 17, 2026
M
Verified Purchase
Matt Stogsdill
Alexandria, US
★★★★★ 4
Cover is nice, keyboard could be better
Color: Navy Blue
The cover itself is nice. The magnetic closure works well. It fits my iPad really well. It’s a good case for the money, but the keyboard feels pretty cheap and flimsy.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 28, 2026

recommand products