SKU: 48122501207

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 Jul 18 - Jul 23

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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: 48122501207

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Michael
Grantham, US
★★★★★ 5
These shoes are great.
Size: 12, Color: Truffle/Ivory
I like the look of these shoes. They can be used for a casual event or even an event that is more formal. They look great with jeans.
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Reviewed in the United States on June 7, 2026
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Mr Friedman
West Palm Beach, US
★★★★★ 5
Beautiful and comfortable
Size: 12 Wide, Color: Black
Beautiful and comfortable
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Reviewed in the United States on May 21, 2026
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DeeDee
Carnegie, US
★★★★★ 5
Really nice
Size: 10.5 Wide, Color: Black
My husband loves these shoes. He has a flat food and said they still fit nice.
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Reviewed in the United States on June 1, 2026
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Brian Diez
Grantham, US
★★★★★ 4
Good Quality
Size: 11, Color: White
Nice looking shoe. Slides on easy. My only feedback would be I wish the toe box was a bit wider and the heel a bit higher. It's a good shoe overall. I would buy again.
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Reviewed in the United States on April 10, 2025
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carl mazaleski
Port Orchard, US
★★★★★ 5
Fit
Size: 11.5 Wide, Color: Cognac
Comfortable and affordable
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Reviewed in the United States on May 14, 2026

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