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LS550 V8 Complete Harness


Shipping Cut-Off:  USPS 9:30am EST / UPS 1:00pm EST

  •  The FuelTech LS550 V8 Complete Harness offers plug and play installation for a standalone LS swap utilizing a FuelTech FT550 or FT550LITE ECU and GM LS engine. The LS550 V8 Complete Harness is pre-terminated for an LS engine installation with all relays and fuses needed for a simple 3 wire battery hook up and ignition power. Ready for both 58x and 24x triggers with provision for direct connection to LS3 style ignition coils, GM style flex fuel sensor and dual WB-O2 Nano connections. The LS550 harness is set up for both cable and drive-by-wire based throttle, with the connector for a GM style accelerator pedal on the cabin side of the harness. Each connector is labeled, and the connectors and harness insulation are heat, moisture and oil resistant. 
  •  LS550 V8 Complete Harness Manual

LS550 V8 Complete Harness Features

      • LS550 V8 LS Complete Harness is designed to install a FuelTech FT550 or FT550LITE ECU on a Chevrolet LS engine when replacing the stock ECU and harness completely. The perfect solution for your LS swap!
      • The LS550 V8 Complete Harness includes all of the connectors needed for a plug and play LS engine installation. It has all the relays and fuses needed for a standard setup, a firewall grommet to hold and seal the harness and each connector is labeled for convenience. 
      • Complete wiring for 8 sequential EV1 injectors (injector sub-harness is not needed). Compatible with high impedance (saturated) injectors and includes wiring for 2 FuelTech Peak and Hold Drivers for use with low impedance (peak and hold) injectors.
      • Compatible with fully sequential OEM LS coils (coil sub harness not required).
      • Compatible with OEM GM pedal and electronic throttle body from the LS2, LS3, LS7, LSA, LS9 and similar as well as cable throttle body when converted from electronic to mechanical throttle.
      • Prewired for most engine sensors: Electronic Pedal, Electronic Throttle body, TPS, 24x or 58x crank trigger, front and rear cam sync (1 and 4 tooth compatible), flex fuel sensor, fuel pressure, oil pressure, coolant and intake air temperature, and more through extra inputs available for custom wiring.
      • Flex Fuel Ready with included connector for the Continental Flex Fuel Sensor
      • This harness is setup for two FuelTech WB-O2 Nano O2 conditioners and two Bosch LSU 4.2 Wideband O2 Sensors.
      • The INPUTS connector allows you to custom wire up to 6 additional input channels for engine or chassis datalogging (i.e. driveshaft RPM, transbrake button, suspension travel sensors, input shaft RPM, staging button and much more)
      • The EXTRA OUTPUTS connector allows you to custom wire up to 8 additional outputs such as wastegate boost control solenoids, transbrake solenoid, dump and lockup valves, gear shift, nitrous stages, and more.
      • Comes with three 40A relays and fuses: The Main Relay powers the ECU, WB-O2 Nano and all sensors. The Second Relay powers the Peak and Hold drivers and fuel injectors. The Third Relay powers the ignition coils.
      • Weight for LS550 V8 Complete Harness: 8 lbs. 3oz

Contents of Packaging

  • 1 LS550 V8 Complete Harness
  • 2 Peak & Hold Jumper Harnesses
  • 1 LS550 8-Way Connector Kit
  • 1 LS550 10-Way Connector Kit
  • 1 LS550 12-Way Connector Kit
  • 1 Operation and Installation Guide