SKU: 170363810

Holley Terminator X MAX Engine Management Systems 550-917

Sale price$899.98 Regular price$999.98
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Ships within 48 hours · Estimated delivery Aug 17 - Aug 22

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Description

Holley Terminator X MAX Engine Management Systems 550-917TERMINATOR X MAX MPFI W TRANS CONTROL Take control of your LS engine with Terminator X Max! 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 Max features real time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable

TERMINATOR X MAX MPFI W/TRANS CONTROL

Take control of your LS engine with Terminator X Max! 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 Max 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. Part number 550-917 also has 4L60E or 4L80E Transmission control. Terminator X Max 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 MAX has the features and technology you need at a price that won't break the bank!

Features:

  • For GM LS 4.8/5.3/6.0 Truck Engines with 24x crank reluctor, Transmission Control, 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 Max systems utilize the Bosch LSU 4.9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control.
  • On-Board 1bar MAP sensor, is perfect for N/A or Nitrous engine combos. If your combination requires a 2+Bar, we recommend GM 12592525, and our adapter part number 558-416.
  • 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 AFRadjustable through included 3.5” full color touchscreen, base tune easily created via handheld Wizard!
  • 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 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 - 4L60E/4L80E Transmission Control Harness - Terminator X MAX ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - Input/Output Harness - and assorted vacuum adapters.

Application

  • 2003 - 2006 Chevrolet Express
  • 2003 - 2006 GMC Savana
  • 1999 - 2006 Chevrolet Silverado
  • 1999 - 2006 GMC Sierra 1500
  • 2000 - 2006 Chevrolet Tahoe
  • 2000 - 2006 GMC Yukon
  • 2002 - 2007 Chevrolet Avalanche
  • 2002 - 2006 GMC Yukon XL 1500
  • 2003 - 2005 Chevrolet TrailBlazer EXT
  • 2003 - 2004 Isuzu Ascender
  • 2003 - 2004 GMC Envoy XL
  • 2003 - 2004 Chevrolet SSR
  • 2004 Buick Rainier
  • 2002 - 2007 Chevrolet Silverado 1500

Specs

Brand Holley EFI
Crank Reluctor 24x
Emission Code 3
Ignition Type GM LS 24x
Injector Connector Multec 2
Product Type Terminator X Max LS MPFI
Terminator LS Options Fuel, Spark, Transmission
Part Number 550-917
    Shipping Notes
    • Free Standard Shipping on $100+ Orders to the USA.
    • Except Preorder products are shipped in 48 hours.
    • Delivery to the USA:
    1. Standard Shipping : 3-10 business days
    • If time is of the essence, please consider selecting expedited delivery for faster service.
    Exchange/Return Notes
    • We offer a 30-day return/exchange service after receiving.
    • Final sale items are not eligible for returns or exchanges.
    • To process your return/exchange, please contact us at [email protected]
    • Please click here for more details>>> Return & Exchange Policy
    SKU: 170363810

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    4.5 ★★★★★
    Based on 10 reviews
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    I
    Verified Purchase
    It's cool.
    Houston, US
    ★★★★★ 4
    Weightless, well made. But there are problems with size
    Size: 8.5, Color: White
    I bought it for a teenager, for size 81/2. This, according to the dimensions on the page, is 25.9 centimeters. They came, the size was indicated correctly, but they are large for the child. Very large. They fit me, size 10. The child is disappointed. Well made, look neat on the foot. Almost weightless But I can't give the maximum rating. I wish the seller to deal with the size grid.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on April 15, 2026
    M
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    Matthew Gonzales
    Lexington, US
    ★★★★★ 5
    Amazing Shoe!
    Size: 9 Wide, Color: Blazer Blue Hand Stain
    Amazing shoe!! Comfortable to wear for long periods of time! Highly recommend!! 👍🏾
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on November 17, 2025
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    William Mantilla
    Alexandria, US
    ★★★★★ 5
    Calzado elegante para oficina de excelente calidad
    Producto de excelente calidad. La entrega fue rápida y el empaque llegó en perfectas condiciones. Cumple completamente con lo descrito en la publicación.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on April 28, 2026
    M
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    MH
    New York, US
    ★★★★★ 3
    Not A Walking Shoe
    Size: 9.5, Color: Black/British Tan
    In the photo online this shoe looks like it will be very comfortable. Kind of a classy Coach's Shoe. Also in the photo the heel portion of the sole looks thick and supportive. I bought them thinking they would be my go-to travel shoe. Wrong. This is not a comfortable shoe for extended wear. Short durations, OK. The main problem is that the sole is very thin and flexible in all directions. There is no, as in zero arch support, plus that thin heel means that you tend to rock back on your heels and it feels like you're pounding the pavement. I've worn once and I'm very disappointed. They look great, definitely high quality materials, but using them for the intended purpose of travel.... fah get about it. If you're looking for a good looking shoe to wear around the gym and you don't intend to use the treadmill, or elliptical, then this is the shoe you want. They would definitely be returned if I hadn't already worn them outside.
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    Reviewed in the United States on August 11, 2023
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    DF
    Lowell, US
    ★★★★★ 5
    Great shoe!
    Size: 14 Wide, Color: Woodbury Handstain
    Great shoe- better leather cover than last pair that scuffed if you blinked at them.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on March 15, 2026

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