SKU: 94576912423

HP EFI ECU & Harness Kits - 550-601N

Sale price$1349.97 Regular price$1499.97
Save 10%

Pay in installments of $374.99 with ShopPay, AfterPay and Klarna

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Aug 5 - Aug 10

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: 94576912423

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.1 ★★★★★
Based on 13 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
F
Verified Purchase
farmer
Los Angeles, US
★★★★★ 5
100 % genuine sheepskin.
Color: Ivory, Size: 2' x 3' (Pelt)
Just received today. Beautiful sheepskin rug. 100 percent natural long fibers. As the listing states..."it has the wrong labei". That must be why the "experts" complained. Out of several rugs i own, this one is the nicest. Slight smell but airing it out will take care of that.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on September 3, 2025
M
Verified Purchase
mparker
Chelsea, US
★★★★★ 4
Overall good quality
Color: Ivory, Size: 2' x 3' (Pelt), Color: Ivory, Size: 2' x 3' (Pelt)
I was pleasantly surprised by the thickness of this rug. No bad smell coming off it. I like the leather backing on it. Wasn't as soft/fluffy straight out the bag but a quick brush fixed that issue for me. So far even with the brushing there is minimal shedding. Bought as a gift for my husband but my son enjoys it.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 9, 2023
C
Verified Purchase
chaindraggone
Boise, US
★★★★★ 5
Soft and easy to comb and fluff again.
Color: Ivory, Size: 2' x 6' (Runner)
This sheep skin fit perfectly in front of DOG'S couch! It is the go to place to curl up or stretch out after tearing up the yard playing!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 11, 2026
P
Verified Purchase
Patricia Jordan
Waukegan, US
★★★★★ 5
Great product: thick and cozy
Size: Single Pelt/2 ft x 3 ft, Color: Natural (Ivory Whiite)
This is a lovely, thick sheepskin. I’m using it to drape over a chair. It’s very soft. The color is a natural white. Arrived quickly. The price was great for such a wonderful sheepskin.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 3, 2026
N
Verified Purchase
Nate B
Boise, US
★★★★★ 5
Love it!
Size: 2' x 6' (Double Pelt), Color: Linen, Size: 2' x 6' (Double Pelt), Color: Linen
Exceeded all expectations. Bigger than I imagined it would be, super soft and thick, beautiful color (Linen), and no funky smell at all. It seems very durable. After running my hands all over it, no shedding occurred. I have yet to sit on it myself, though, as my cat claimed it right away - didn't even wait for me to remove the tag! He's been there for hours and I'm thinking I've lost my snuggle buddy, so I bought two more in the smaller size so he can have his own on the bed with me at night. I am so amazed by the quality, feel, and color. I can't believe I almost let other reviews deter me from this purchase. 100% thrilled with this beautiful pelt. Absolutely recommend! UPDATE: I received the other 2 purchased. Just as soft, just as thick, consistent color (Linen), no shedding, no smell. They have been in use for several days now without any issues. Love them all - and my snuggle buddy is back! 🥰
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 22, 2024

recommand products