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Description
HP EFI ECU & Harness Kits - 550-603NOverview: 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! Features: Simple Installation Plug and Play control of GM LS2 LS3 LS7 engines. Just plug the harness into your factory
Overview:
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!
Features:
- Simple Installation - Plug and Play control of GM LS2/LS3/LS7 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, USCAR (EV6 Style) injector connectors, and NTK wideband O2 sensor, designed to be used with GM LS2/LS3/LS7 engines with factory GM coils and a 58 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" touch screen 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:
| Year | Make | Model | Submodel | Engine Size |
|---|---|---|---|---|
| Universal |
Specs:
| Brand | Holley EFI |
|---|---|
| Crank Reluctor | 58x |
| Emission Code | 4 |
| Ignition Type | GM LS 58x |
| Injector Connector | USCAR (EV6) |
| Product Type | HP EFI Kit |
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
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Exchange/Return Notes
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- Final sale items are not eligible for returns or exchanges.
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★★★★★ 5
Great book!
Format: Paperback
Great book!
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Reviewed in the United States on February 16, 2026
★★★★★ 5
great price
Format: Paperback
Interesting read.
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Reviewed in the United States on January 14, 2026
★★★★★ 5
An outstanding spiritual treasure trove
Format: Paperback
This book is a treasure of spiritual insights and guidelines to live a devout life. Although written hundreds of years ago, it is remarkably apt and relevant today. St. Francis de Sales was a spiritual director, and it is clear why he was so sought after and valued. This book is one I turn to again and again as life circumstances change, and I have given away copies to several fellow pilgrims. This spiritual classic receives my highest endorsement.
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Reviewed in the United States on May 25, 2025
★★★★★ 5
100% Yes!
Format: Paperback
Every Christian should read this book! Revitalized my prayer and contemplation, St. Francis de Sales really walks you through the steps of seeking Christ in new ways.
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Reviewed in the United States on August 28, 2025
★★★★★ 5
Something for everyone….
Format: Paperback
Awesome book…lots of great spiritual advice and inspirations.
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Reviewed in the United States on August 21, 2025