Holley EFI Terminator X - Gen III 4.8/5.3/6.0 GM Truck Engines 550-904T
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Features:
- For GM LS Engines with 24x crank reluctor and Multec 2 Injectors
- Real-Time fuel map learn, takes the guess work out of tuning your base fuel table.
- High Impedance Injector Drivers will safely power most Stock LS injectors, and Holley EFI Injectors. Injector support chart provided in the instructions (Will not control Low Impedance Injectors)
- All of the new Terminator X systems utilize the Bosch LSU 4.9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control.
- MAP Sensor vacuum hose adapters (1/8th Ð _ and 3/16ths)
- 4 Outputs Ð Ground, PWM - , for accessories such as; fans, boost control, nitrous control, IAC Kit, and More
- 4 Inputs Ð 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
- Boost Control Ð Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties
- Nitrous Control Ð Single Channel of Wet or Dry, Progressive or Non-Progressive, Rich/Lean Safeties, and target Closed Loop AFR
- On-Board Diagnostic LEDS for: ECU Power Ð Engine Run Ð Wideband Status Ð TPS Calibration Ð Crank Signal ÐCam Signal. Allow you to identify any Critical engine issues at a glance
- Advanced Tables Ð 4x 1D Tables, 1x 1D per Gear Table, 4x 2D Tables, 1x 2D per Gear Table, can be used for any custom tables you can dream up, such as Flex Fuel Sensor Offset Table, or a custom fuel or oil pressure safety!
- Includes CAN/USB tuning cable allowing you to configure your ECU and Tuning the engine in real time.
- The compact ECU size allows you to mount it virtually anywhere. Remember, diagnostic LEDS must face up!
- Plug and play compatible with multiple Holley EFI accessories including our gauges, shift lights, various modules, and digital and pro dashes (Holley P/N's 553-106, 553-111, and 553-112)
- Free EFI Tuning Software for complete control of your Terminator X power plant
- Includes: 24x LS Engine Main Harness - Multec 2 Injector Harness - Terminator X ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - Input/Output Harness - and assorted vacuum adapters.
About Holley EFI

Find standalone EFI for LS, Coyote, Hemi and more at Holley.com. From engine swapping to managing up to 4000 horsepower, we have a solution for every project!
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