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Holley EFI Terminator X - Gen III 4.8/5.3/6.0 GM Truck Engines

24x Crank - 1x Cam - Multec 2 Injectors - 3.5 in. Touchscreen

Injector Connector

Crank Reluctor

Drive-By-Wire

Handheld Included

Transmission

Part # 550-904
17 Reviews

Holley EFI Terminator X - Gen III 4.8/5.3/6.0 GM Truck Engines

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$1,427.95
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3

Emissions

This part is legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles.

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Take control of your LS engine with Terminator X! Don't settle for a junkyard ECU with a cumbersome tuning interface when you can have complete control of your engine, self-learning fuel strategies and the proven, race-winning technology of Holley EFI at a budget-friendly price! Terminator X features real-time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs and outputs. The inputs and outputs are ideal for electric fans, boost control solenoids, progressive nitrous control, and much more. Terminator X comes fully loaded with base maps for common LS engine combinations to get you out of the garage and on the road/track fast. The 3.5" touch screen LCD handheld contains an easy to use calibration wizard as well as tuning and gauge display functions. Also included is Holley EFI's industry-leading, easy to use software suite that allows full laptop access for advanced users. Whether you are building a budget beater or a boosted race car, Terminator X has the features and technology you need at a price that won't break the bank!

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 – ¼ and 3/16ths)
  • 4 Outputs – Ground, PWM - , for accessories such as; fans, boost control, nitrous control, IAC Kit, and More
  • 4 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
  • Boost Control – Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties
  • Nitrous Control – 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 – Engine Run – Wideband Status – TPS Calibration – Crank Signal –Cam Signal. Allow you to identify any Critical engine issues at a glance
  • Advanced Tables – 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!adjustable through included 3.5” f
  • The included 3.5" Touchscreen Handheld contains a calibration wizard, that allows you to quickly build a base tune for any LS engine. Additionally the handheld provides internal data-logging and a fully customizable gauge display.
  • The compact ECU size allows you to mount it virtually anywhere. Remember, diagnostic LEDS must face up!
  • Plug and play compatible with more Holley EFI accessories such as; analog style gauges, shift lights, various modules, and coming soon, 12.3" digital dash support!
  • 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

Holley is the new standard in EFI! Whether you're engine swapping your classic car or need to manage 4000 horsepower in your twin-turbocharged drag radial race car, Holley EFI has the solutions you need to get your project up and running better than ever!

Brand Holley EFI
Crank Reluctor24x
Drive-By-WireNo
Emission Code3
EngineGen III GM Truck
Handheld IncludedYes
Ignition TypeGM LS 24x
Injector ConnectorMultec 2
Product TypeEFI System
Terminator LS OptionsFuel, Spark
TransmissionNone
UPC090127060803
Part Number550-904
3

This part is legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles.


The following vehicles are considered Uncontrolled (Non-Emissions Controlled) Vehicles:

  • 1965 and older U.S. manufactured California Certified vehicles
  • 1967 and older U.S. manufactured Federally Certified vehicles
  • 1967 and older Foreign manufactured vehicle


WARNING: It is against the law to install this part on an Emissions Controlled Vehicle


The following vehicles are considered Emissions Controlled Vehicles:

  • 1966 and newer U.S. manufactured California Certified vehicles
  • 1968 and newer U.S. manufactured Federally Certified vehicles
  • 1968 and newer Foreign manufactured vehicle
Holley EFI Dealers
Do you need a custom kit built for your application? Do you need a system installed and tuned? Click here to find the Holley EFI dealer in your area!
Wiring Diagram
LS1 Main Harness
Terminator X ECU's are designed to be mounted with the LED's facing up.
Reviews
17

4.9 out of 5 stars

  • 5 star

    94%

  • 4 star

    6%

  • 3 star

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Some parts are not legal for use in California or other states with similar regulations.