The Holley HP EFI ECU and harness kit gives GM LS1/LS6 owners a plug-and-play way to control fuel and ignition, with room to grow into boost, nitrous, or water/meth control as the build evolves. Download a base map for a stock LS engine and drive, or dial in a turbocharged, nitrous-fed combination running on water/meth — the same ECU handles both without constant re-flashing.
Key Features:
- ECU certified to ISO 8846, SAE J1171, and U.S. Coast Guard requirements for ignition protection and fire resistance
- 1-5 Bar MAP sensor capability
- Laptop-programmable with a variety of included base maps
- Sealed automotive and marine-grade connectors
- NTK oxygen sensor recommended for leaded or methanol fuels, high exhaust temperatures, and forced induction applications
- ECU is fully potted for engine bay or interior mounting
- Self-tuning fuel strategy reduces time spent tuning
- More functionality than OEM or competing ECUs — boost control, nitrous control, water/meth injection, and more
- Simple plug-and-play installation into factory sensors, power, and grounds
- Optional plug-and-play handheld programmer, 5.7" touchscreen, and digital gauges available
- Kit includes ECU, harness, communication cable, software, and NTK wideband O2 sensor
- 4 programmable inputs and 4 programmable outputs for boost control, progressive nitrous, water/meth injection, and more
Specifications:
- Engine Platform: GM LS1/LS6
- Crank Reluctor: 24x
- Ignition Type: GM LS 24x
- Injector Connector: Jetronic/Minitimer (Bosch type)
- Inputs/Outputs: 4 programmable inputs, 4 programmable outputs
- MAP Sensor: 1-5 Bar
- Oxygen Sensor: NTK
- What's Included: ECU, harness, communication cable, software, NTK wideband O2 sensor
- Part Number: 550-602N
If more than 4 inputs and 4 outputs are needed for the planned combination of controls, Holley recommends stepping up to the Dominator VMS.
FAQ
What engines does the 550-602N fit?
It's designed for GM LS1/LS6 engines with a 24x crank sensor and Jetronic/Minitimer (Bosch-type) injector connectors.
Do I need a laptop to use this ECU?
The ECU is laptop-programmable and ships with a variety of base maps, though an optional plug-and-play handheld programmer, 5.7" touchscreen, and digital gauges are also available.
Can this ECU control more than fuel and ignition?
Yes. It has 4 programmable inputs and 4 programmable outputs that can support boost control, progressive nitrous, water/meth injection, fan control, and more.
What's included in the kit?
The kit includes the ECU, harness, communication cable, software, and an NTK wideband oxygen sensor.
What if I need more inputs and outputs than this kit offers?
Holley recommends the Dominator VMS if your combination of controls requires more than the 4 inputs and 4 outputs on this HP EFI kit.
