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 Sep 17 - Sep 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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    4.2 ★★★★★
    Based on 11 reviews
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    E
    Verified Purchase
    E…
    Phoenix, US
    ★★★★★ 5
    great purchase
    Color: Scrunch Bunch Duck
    great dog toy! my dogs love playing with it! what shipped out to me in a very timely manner and was delivered in perfect conditions.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on May 7, 2026
    P
    Verified Purchase
    priscilla
    Chelsea, US
    ★★★★★ 5
    My yorkie destroyed
    It says it’s very durable so that’s why I bought it although the body and ropes are good the ears on the horse came off in the first day with my small dog so be careful with the ears and other looser things on the animals. The rope untied many times as well not a big deal I just knotted it back but she still loves this toy so it’s okay I’m my book just watch for ripping of ears and other parts on the head of this toy
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on March 2, 2023
    K
    Verified Purchase
    K. B.
    Cuba, US
    ★★★★★ 1
    Head and body ripped after less than 5 min of tug
    Color: Scrunch Bunch Bunny, Color: Scrunch Bunch Bunny
    The seam beteeen the head and body failed after less than five minutes of supervised tug with a 35 pound dog. This is NOT a tough toy. No reinforced stitching. Absolutely unsafe - a dog could easily rip open the neck and get at the squeakers, which are small enough to be swallowed and lodged in an intestine.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on April 22, 2026
    M
    Verified Purchase
    Melissa Caban
    Draper, US
    ★★★★★ 3
    Good but not as tough as advertised
    Color: Scrunch Bunch Duck
    My dog absolutely loved this toy. He was obsessed immediately! It was his (and our) first crinkle toy. He loves the crinkle though it’s a bit distracting for me as it kind of sounds like he’s getting into something he shouldn’t. I love that there are two squeakers, one in the belly and one in one of the handles to squeak on during tug of war. Though he enjoys this toy, the head ripped off during a mild tug only about a few hrs after delivery. My dog is a medium sized 25 lb dog, he is not super strong or a super chewer by any means so I was surprised that it tore so easily. The fabric itself seems strong enough to withstand mild chewing but the seams aren’t as tough as they are advertised. If you don’t mind mending your dogs toys, it’s a very fun toy that’s easy to play with your dog as the handles work well for tug of war, just keep in mind that anything over a small sized dog will probably tear this toy apart during a play session.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on August 22, 2025
    M
    Verified Purchase
    Madison
    Phoenix, US
    ★★★★★ 5
    Great dog toy
    Color: Ranch Roperz Cow
    Perfect puppy toy, not too loud, durable for chewing, soft enough for sensitive mouths! Great size for all dogs to have fun!
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on January 25, 2026

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