Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8 by Holley

Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8
Holley EFI Ford Terminator X MPFI Master Kit 5.0/5.8

Transform the efficiency of your Ford 5.0L or 5.8L Windsor power plant with the help of Holley's Terminator X MPFI kit from Late Model Restoration!

Item #HLY-550937-K

Everyday Low Price: $2,146.45

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  • 5.0 HO EFI-specific Kit
  • Real-Time Self-Learning Fuel Strategies
  • Built-In Boost & Nitrous Control
  • Plug & Play Harnesses
  • On-Board Diagnostics


  • Pre-Loaded With Base Maps For Common V8 Combinations
  • High Impedance Injector Drivers
  • Customizable Gauge Display
  • Built-In 1 Bar MAP Sensor

 What's in the Box

  • (1) Terminator X ECU
  • (1) 3.5" Touchscreen LCD Handheld
  • (1) TFI Ignition Adapter
  • (1) Primary Engine Harness
  • (1) EV1 Injector Harness
  • (1) Bosch LSU 4.9 Wideband Oxygen Sensor
  • (1) Built-In 1 Bar Manifold Absolute Pressure Sensor
  • (1) Manifold Air Temperature Sensor
  • (1) Crank Sensor Vacuum Hose Adapters
  • (1) Input/Output Harness
  • (1) Coolant Temp Sensor

Holley EFI Ford Terminator X MPFI Kit
Take control of your EFI Equipped 5.0 or 5.8 Ford Windsor engine and transform the power, efficiency, and drivability with Holley's Terminator X EFI Kit! Late Model Restoration took this kit a step further, adding in all the correct wiring harnesses, sensors, and adapters needed to control a 5.0 HO EFI-specific engine. Control your engine, self-learning fuel strategies, and the proven, race-winning technology of Holley's EFI at a budget-friendly price! The Terminator X features real-time fuel learning, high impedance injector drivers, an integrated 1 bar MAP sensor, and 4 programmable inputs and outputs. Inputs and outputs are ideal for electric fans, boost control solenoids, progressive nitrous control, and much more. This Terminator X comes fully loaded with base maps for common V8 engine combinations to get you out of the garage and on the road/track fast! The 3.5" touchscreen LCD handheld device contains an easy-to-use calibration wizard as well as tuning and gauge display functions. Holley EFI's industry-leading, easy-to-use software is provided to allow full laptop access for advanced tuning. This Holley Terminator X EFI kit is the perfect solution for an engine-swapped classic car or competition race car, thanks to its impressive features and technology that won't break the bank!

More Complete System
This kit is more than just the base Holley's Terminator X kit; it comes with all of the correct 5.0 HO EFI-specific harnesses, adapters, and sensors for a factory-style 5.0 EFI engine. A plug-and-play with fuel-injected 5.0 small block Ford engine main harness, TFI distributor adapter harness, and input/output adapter harnesses means minimal wiring. Pre-terminated with Ford PWM IAC connector for the OEM PWM idle air control motor. Holley Terminator-specific coolant temperature and intake air temperature sensors help finish out your installation. All of these parts are needed to get you up and running in no time at all!

Additional Components
  • 5.0 Specific Main Harness - 558-128
  • TFI Ignition Adapter - 558-305
  • Coolant Temp Sensor - 543-120
  • Intake Air Sensor - 534-20
  • I/O Harness - 558-462
  • EV1 Injector Harness

Full List of Features

  • NOT for emission-compliant applications.
  • This is a NO LAPTOP REQUIRED kit! Simply enter the information about your specific engine combination into the wizard on the 3.5" handheld touchscreen and the ECU will build a tune map around your specifications the more the car is driven! No need to be an EFI or tuning expert!
  • High Impedance Injector Drivers will safely power most Stock 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.
  • Built-in 1bar MAP Sensor, vacuum hose adapters included (1/8th – ¼ and 3/16ths) - or for Boosted applications, you can disable the internal MAP sensor, and utilize an external MAP Sensor, the harness comes with the connector terminated, making the install.
  • MAP Sensor vacuum hose adapters (1/8th – ¼ and 3/16ths)
  • Plug and plug ignition capability with Dual Sync and HyperSpark Distributors, adapter 558-323 required for HyperSpark Distributors.
  • 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.
  • 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!
  • 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.
  • The included 3.5" Touchscreen Handheld contains a calibration wizard that allows you to quickly build a base tune for any domestic V8 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.

This product is intended for off-road use only, and is not legal for use in emission restrictive states. Off-Road Disclaimer

Holley Warranty - Click Here

Fitment Notice
  • NOT for emissions-compliant applications!
  • Fits 5.0L and 5.8L Windsor engines.
  • Due to the custom nature of this product, please be sure to read all installation manuals provided.
  • Terminator X ECU's are designed to be mounted with the LED's facing up.
  • Safely mount the ECU in your 1979-2004 Mustang using the Holley mounting bracket.

California Residents:
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About This Brand

Holley, The Heart & Soul of Performance.

For over 100 years Holley has been proven to be an industry leader by providing Mustang enthusiasts and racers with the high performance carburetors , intake manifolds, cylinder heads, and other quality performance components needed for today's competition. Holley's performance Mustang parts are perfect for any daily driven or high horsepower race car.
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