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Holley EFI 550-603 HP EFI ECU & Harness Kits

Name: Holley EFI 550-603 HP EFI ECU & Harness Kits
Brand: HOLLEY EFI
SKU: 108129830
Price: 2719.95 USD
Availability: InStock

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Key item features

Simple Installation: Offers plug-and-play control for LS2/LS3/LS7 engines, requiring only connection to factory sensors and power/ground wiring.
Enhanced Functionality: Provides advanced controls including boost, nitrous, water/meth injection, and additional inputs/outputs for fans, pumps, and relays.
User-Friendly Tuning: Laptop programmable ECU includes base maps for quick setup, complemented by an industry-leading self-tuning fuel strategy.
Versatile Application: Suitable for a wide range of uses, from stock 5.3L engine swaps to high-horsepower race cars.
Comprehensive Kit: Includes the ECU, harness, communication cable, software, USCAR (EV6 Style) injector connectors, and a wideband O2 sensor.
Durable Design: Features a fully potted ECU for engine compartment or interior mounting and sealed automotive/marine grade connectors.
Safety Certified: ECU is certified to ISO 8846, SAE J1171, and United States Coast Guard requirements for ignition protection and fire resistance.

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Specs

Vehicle make
GM
Vehicle model
LS2
Automotive electrical part & accessory type
Modules
Compatibility
GM LS2, Holley C950
Compatible cars
GM LS2/3/7 Engine
Vehicle fitment type
Specific

Current price is $2,719.95

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About this item

Product details

Compatible with GM LS2/3/7 Engine - (58x crank sensor) with USCAR (EV6 Style) connectors on injector harness, Includes Bosch Oxygen Sensor;

Looking for a plug and play alternative for your stock or built late model factory EFI engine? How about a replacement ECU for your older Holley C950? Holley has you covered. HP EFI ECU and harness kits are designed to be used with popular factory EFI engines as an alternative to the factory ECU and harness or as a replacement for your C950 ECU. The HP allows you to accurately control the fuel and ignition of your engine along with additional controls for NOS, boost, or water meth.;

Simple Installation - Plug and Play control of 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 factory 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 wideband O2 sensor, designed to be used with LS2/LS3/LS7 engines with factory 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!

info:

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Specifications

Vehicle make

Vehicle model

LS2

Automotive electrical part & accessory type

Modules

Compatibility

GM LS2, Holley C950

Warranty

Warranty information

xxxx

Please be aware that the warranty terms on items offered for sale by third party Marketplace sellers may differ from those displayed in this section (if any). To confirm warranty terms on an item offered for sale by a third party Marketplace seller, please use the 'Contact seller' feature on the third party Marketplace seller's information page and request the item's warranty terms prior to purchase.

Warranty url

https://www.nosoemparts.com/pages/returns

Warnings

Warning Text

California Proposition 65

WARNING: Cancer and Reproductive Harm - www.P65Warnings.com

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Comparison Chart:
Vehicle make	GMHolley EFI 550-603 HP EFI ECU & Harness Kits	BOSCHHolley EFI 550-607 HP EFI ECU & Harness Kits	FordHolley EFI 550-606 HP EFI ECU & Harness Kits	RAMHolley EFI 550-601N HP EFI ECU & Harness Kits	GMHolley EFI 558-220 GDI Sub Harness - Early LTx Engine	GMHolley EFI 558-221 GDI Sub Harness - Late LTx Engine	GMHolley EFI 550-605N HP EFI ECU & Harness Kits	GMHolley EFI 550-602 HP EFI ECU and Harness Kits	FordHolley EFI 558-505 HP & Dominator ECU - EFI Harness Kit	GMTerminator® LS MPFI
Vehicle model	LS2Holley EFI 550-603 HP EFI ECU & Harness Kits	LS2/3/7Holley EFI 550-607 HP EFI ECU & Harness Kits	V8Holley EFI 550-606 HP EFI ECU & Harness Kits	TPIHolley EFI 550-601N HP EFI ECU & Harness Kits	LTxHolley EFI 558-220 GDI Sub Harness - Early LTx Engine	LTxHolley EFI 558-221 GDI Sub Harness - Late LTx Engine	LS2Holley EFI 550-605N HP EFI ECU & Harness Kits	LS1/LS6Holley EFI 550-602 HP EFI ECU and Harness Kits	-Holley EFI 558-505 HP & Dominator ECU - EFI Harness Kit	LSTerminator® LS MPFI
Automotive electrical part & accessory type	ModulesHolley EFI 550-603 HP EFI ECU & Harness Kits	ConnectorsHolley EFI 550-607 HP EFI ECU & Harness Kits	ModulesHolley EFI 550-606 HP EFI ECU & Harness Kits	ModulesHolley EFI 550-601N HP EFI ECU & Harness Kits	WiresHolley EFI 558-220 GDI Sub Harness - Early LTx Engine	WiresHolley EFI 558-221 GDI Sub Harness - Late LTx Engine	ModulesHolley EFI 550-605N HP EFI ECU & Harness Kits	ModulesHolley EFI 550-602 HP EFI ECU and Harness Kits	WiresHolley EFI 558-505 HP & Dominator ECU - EFI Harness Kit	ModulesTerminator® LS MPFI
Compatibility	GM LS2, Holley C950Holley EFI 550-603 HP EFI ECU & Harness Kits	GM LS2/LS3/LS7Holley EFI 550-607 HP EFI ECU & Harness Kits	-Holley EFI 550-606 HP EFI ECU & Harness Kits	-Holley EFI 550-601N HP EFI ECU & Harness Kits	Early GM Gen V LTx EnginesHolley EFI 558-220 GDI Sub Harness - Early LTx Engine	Late GM Gen V LTx EnginesHolley EFI 558-221 GDI Sub Harness - Late LTx Engine	Holley C950Holley EFI 550-605N HP EFI ECU & Harness Kits	GM LS1/LS6 enginesHolley EFI 550-602 HP EFI ECU and Harness Kits	-Holley EFI 558-505 HP & Dominator ECU - EFI Harness Kit	-Terminator® LS MPFI