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Ships within 48 hours Β· Estimated delivery Jul 15 - Jul 20
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Description
Holley HP EFI ECU and Harness Kits 550-603HP ECU AND HARNESS LS2 & LS7 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
HP ECU AND HARNESS LS2 & LS7
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 Bosch wideband O2 sensor, designed to be used with GM LS2/LS3/LS7 engines with factory GM coils and a 58 tooth crank sensor
- 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!Β
Application
- 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 |
| Part Number | 550-603 |
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- 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
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5
Beautiful and very easy to install
Size: 4 pcs: 15.7*5.7, Color: White
They look great and very easy to install, I really recommend this product.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 28, 2026
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3
Just Ok.
Size: 4 pcs: 15.7*5.7, Color: Maple Wood, Size: 4 pcs: 15.7*5.7, Color: Maple Wood
They look nice but they arenβt sturdy and do not hold much weight. Iβve bought better ones on Amazon.
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Reviewed in the United States on January 12, 2026
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5
Worth
Size: 6 pcs: 15.7*5.7, Color: White
Really good wall amounts. I used the drywall anchors and it feels sturdy. I put like a 3 pound Crystal on it and itβs holding perfectly fine. I also was able to paint them with no problem would buy again.
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Reviewed in the United States on January 13, 2026
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5
great shelves
Color: C. White - Modern Minimalist Style, Number Of Shelves: 3, Size: 36inches
These are a a great set of floating shelves! They were easy to install, feel sturdy, and look clean and modern on the wall. The set of three is perfect for displaying decor, photos, plants or small storage items while adding extra space without taking up room. Great quality, stylish, and a simple way to upgrade any space. They work perfect for my figurines to be displayed.
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Reviewed in the United States on May 19, 2026
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5
Great shelves
Color: A. Black - Universal Classic Style, Number Of Shelves: 3, Size: 22.5inches
Easy to hang and look great in my office. I love the little divot along the edge. Helps to keep pictures from sliding.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 29, 2026
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