SKU: 91453434761

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 Oct 9 - Oct 14

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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: 91453434761

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    4.6 ★★★★★
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    Verified Purchase
    CW
    Los Angeles, US
    ★★★★★ 5
    Almost Perfect
    Color: Pink+purple
    EDITED TO ADD: the seller reached out after I left this review and told me the heads are replaceable! Mine didn't come with extra heads and I didn't realize they came off. Thank for reaching out! It looks like the product even comes with replacement heads now and you can also buy them separately. Perfect! These are great. _________ My kids love these toothbrushes and I love that they're rechargeable without needing batteries. However, the charging feature is almost completely negated by the fact that you can't replace the heads! It would be a 5 star if you could swap those out.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on April 16, 2026
    C
    Verified Purchase
    CD
    Boise, US
    ★★★★★ 5
    Very cute and effective!
    Color: Pink+purple, Color: Pink+purple
    Very cute and effective brush! I love that there are different settings for different ages and the lowest is soft enough for my 3 year old. She LOVED choosing from the stickers to put on and there’s more left over for when she wants to change them. Stays charged for quite a long time. Would repurchase!
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    Reviewed in the United States on April 30, 2026
    G
    Verified Purchase
    Great camera, easy to set up. Clear picture and the spotlight is great for night time.
    Lake Worth, US
    ★★★★★ 5
    Perfect kids electric toothbrush
    Color: Pink+purple
    My child loves this toothbrush. I love that it’s rechargeable and comes with extra brush heads. Very suitable for kids and a great value.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on April 1, 2026
    D
    Verified Purchase
    Dymm Witt
    Alexandria, US
    ★★★★★ 4
    Good quality toothbrush. However..
    Color: Pink+purple
    Got this for our 3-year-old granddaughter who needs to keep her teeth clean. Problem is, it tickles her teeth so is not used to the extended should be. Don't know how to solve that issue, but it is a good toothbrush.
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on May 20, 2026
    M
    Verified Purchase
    mbal09
    Lexington, US
    ★★★★★ 5
    Kids Toothbrush
    Color: Red+blue
    Purchased this toothbrush for my 5yr old! He loves it especially because it comes in his favorite colors. The prices is great as well! The charge lasts forever. I have only charged it once since I purchased. I purchased it for travel through Europe so I could throw out the toothbrush heads. The customer service is 10/10. Reached out regarding replacement brush heads because I know my son will throw a fit if they aren’t the same ones and told us they will be available for purchase and sending us some in the meantime. So now I will also be purchasing the matching water flosser!
    WAS THIS REVIEW HELPFUL?YesReportShare
    Reviewed in the United States on January 28, 2026

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