Holley 550-603 HP EFI ECU & Harness Kit, LS2/LS3/LS7, Bosch O2

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!

• 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!

Installation Instructions (PDF)

Installation Instructions (PDF)