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Holley EFI Terminator X - Gen IV 4.8/5.3/6.0 GM Truck Engines and LS2/LS3

58x Crank - 4x Cam - EV6 Injectors - USB/CAN Tuning Cable

Injector Connector

Crank Reluctor

Drive-By-Wire

Handheld Included

Transmission

Part # 550-905T
17 Reviews

Holley EFI Terminator X - Gen IV 4.8/5.3/6.0 GM Truck Engines and LS2/LS3

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$1,370.95
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3

Emissions

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

See Emissions Details
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. These Terminator X kits include a USB/CAN tuning cable instead of the 3.5" Handheld LCD, these kits require the use of the free Terminator X Software for initial setup. The Terminator X Software includes multiple base calibrations to choose from for either naturally aspirated or boosted engines. 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:

  • Designed for GM LS Engines with 58x Crank, 4x Cam - and EV6 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 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
  • 4 Outputs – Ground, PWM - , for accessories such as; fans, boost control, nitrous control, IAC Kit, and More
  • 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!
  • 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 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: 58x/4x LS Engine Main Harness - EV6 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!

Brand Holley EFI
Crank Reluctor58x
Drive-By-WireNo
Emission Code3
EngineGen IV GM LS
Handheld IncludedNo
Ignition TypeGM LS 58x
Injector ConnectorUSCAR (EV6)
Product TypeEFI System
Sale CategoryAir and Fuel Delivery
Terminator LS OptionsFuel, Spark
TransmissionNone
UPC090127074480
Part Number550-905T
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
LS2 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.