SKU: 84118652470

Holley HP EFI ECU and Harness Kits 550-602N

Sale price$1394.97 Regular price$1549.97
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Ships within 48 hours · Estimated delivery Sep 19 - Sep 24

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Description

Holley HP EFI ECU and Harness Kits 550-602NHP ECU AND HARNESS, LS1 6, NTK Looking for a plug and play kit for your GM LS engine? The HP ECU allows you to accurately control the fuel and ignition of your engine plus much more! Got a stock LS engine? Simply download a base map and you're on your way. Got a turbocharged, nitrous fed LS engine on water meth? This HP EFI kit can control that too! Stop reflashing your factory ECU every time you make a performance modification. Get Holley EFI today!

HP ECU AND HARNESS, LS1/6, NTK

Looking for a plug and play kit for your GM LS engine? The HP ECU allows you to accurately control the fuel and ignition of your engine plus much more! Got a stock LS engine? Simply download a base map and you're on your way. Got a turbocharged, nitrous fed LS engine on water/meth? This HP EFI kit can control that too! Stop re–flashing your factory ECU every time you make a performance modification. Get Holley EFI today!

Features:

  • Simple Installation - Plug and Play control of GM LS1/LS6 engines. Just plug the harness into your factory sensors, wire the power and grounds and you are ready to take complete control of your LS engine
  • More Functionality - Provides significantly more functionality than OEM or other competitive ECUs (boost control, nitrous control, water/meth injection, plus a host of additional inputs and outputs to control fans, pumps, relays etc.)
  • Easy To Use - Laptop programmable ECU includes a variety of base maps that will have you hitting the cruise or track in no time
  • Ideal For Everything - including stock 5.3L engine swaps or all out, 3,000+ horsepower race cars that need a simple and powerful ECU and harness solution
  • Industry Leading Self Tuning Fuel Strategy - means less time tuning and more time enjoying the power of your LS vehicle
  • Kit includes ECU, harness, communication cable, software and and NTK wideband 02 sensor designed to be used with GM LS1/LS6 engines with factory GM coils and a 24 tooth crank sensor
  • The NTK Oxygen Sensor is recommended when using leaded or methanol fuels, high exhaust temperatures and forced induction applications or for highest precision feedback
  • ECU is fully potted and can be mounted in the engine compartment or interior
  • Sealed automotive and marine grade connectors
  • 1-5 Bar MAP sensor capability
  • Optional plug and play hand-held programmer, 5.7" touchscreen and digital gauges are available for ultimate control and vehicle monitoring
  • ECU is certified to ISO 8846, SAE J1171 & United States Coast Guard Requirements for Ignition Protection & Fire Resistance
  • For a full list of advanced features such as boost, nitrous, water/meth, individual cylinder control and more click the document icon under the product image!

Application

  • Universal 

Specs

Brand Holley EFI
Crank Reluctor 24x
Emission Code 4
Ignition Type GM LS 24x
Injector Connector Jetronic / Minitimer (Bosch)
Product Type HP EFI Kit
Part Number 550-602N
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: 84118652470

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Ms. Jackson
Charlottesville, US
★★★★★ 5
If Fluffy was a person lol
Color: Blue, Color: Blue
Came vacuum sealed. No smell. I ABSOLUTELY LOVE how fluffy it is!!! The color is a perfect match to my car. I don’t have an emergency break lever so I couldn’t use that. Overall 10 out of 10 rt now!
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Reviewed in the United States on May 15, 2026
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Lelee
Waukegan, US
★★★★★ 4
Cute lil shedding but it’ll do 🩷
Color: Hot Pink, Color: Hot Pink
Cute I love it looks good 🩷🩷🩷🩷 lil shedding but it’ll do
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Reviewed in the United States on May 2, 2026
B
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Brittney k
Natrona Heights, US
★★★★★ 5
Yes get this one!
Color: Pink
Oh yes this is a good one! So fluffy, and perfect, it came with a sample of real vs fake fur, and it was vacuum sealed, packaging is 10/10 and quality is amazing, thank you!
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Reviewed in the United States on May 3, 2026
B
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Brian & Renee Sitko
Fort Morgan, US
★★★★★ 5
Love the color
Color: Red, Color: Red
Super vibrant color with minimal shedding .. it fits my steering wheel and easy to install and worth the money..
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Reviewed in the United States on May 17, 2026
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T
Louisville, US
★★★★★ 3
It’s ok
Color: Lavender Purple
Its ok. Not as fluffy as i think it would be. I have had it over a month or so and its starting to get even more less fluffy. The color wAs more like a faded purple
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Reviewed in the United States on May 27, 2026

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