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Holley 550-602N EFI ECU & Harness Kits, Includes NTK Oxygen Sensor
Holley 550-602N EFI ECU & Harness Kits, Includes NTK Oxygen Sensor

Holley 550-602N EFI ECU & Harness Kits, Includes NTK Oxygen Sensor

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Holley 550-602N EFI ECU & Harness Kits, Includes NTK Oxygen Sensor
Holley 550-602N EFI ECU & Harness Kits, Includes NTK Oxygen Sensor
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We estimate this item will ship on or before March 26th.
Part # 425550602N
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  • This item ships directly from the manufacturer. It may take an additional 2 business days for Holley to ship this item.
  • Get FREE shipping when your order includes this item and exceeds $99! Ground shipping only in the contiguous US.
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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!

  • 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 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!

Installation Instructions (PDF)

Installation Instructions (PDF)

Some parts are not legal for use in California or other states with similar laws/regulations

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