SKU: 5298063327

Holley Terminator X MAX Engine Management Systems 550-918

Sale price$899.98 Regular price$999.98
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Ships within 48 hours · Estimated delivery Jul 26 - Jul 31

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Description

Holley Terminator X MAX Engine Management Systems 550-918TERMINATOR 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 550-918 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:

  • Designed for GM LS 4.8/5.3/6.0 LS Truck Engines and LS2/LS3 with 58x Crank, 4x Cam and 4L60E/4L80E transmissions, 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 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 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 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: 58x/4x LS Engine Main Harness - EV6 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.

    Specs

    Brand Holley EFI
    Crank Reluctor 58x
    Emission Code 3
    Ignition Type GM LS 58x
    Injector Connector USCAR (EV6)
    Product Type Terminator X Max LS MPFI
    Terminator LS Options Fuel, Spark, Transmission
    Part Number 550-918
    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: 5298063327

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    Mel H.
    Cuba, US
    ★★★★★ 5
    Quality item and super comfy.
    Size: XX-Large, Color: Light Grey Heather
    Got this for my son to take on a field trip in case it got lost it wasn’t one of his expensive ones. Oddly enough it’s so comfy it’s now his favorite hoodie and he wears it all the time and keeps it in his backpack. Holds up well to constant washing.
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    Reviewed in the United States on May 18, 2026
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    Harper
    Whiting, US
    ★★★★★ 5
    WARM, not thin material
    Size: Small, Color: Blue
    Hoodie is comfy, warm and soft. Fits true to size, especially for a child who is a bit small for their age. Holds its' integrity in the wash. VERY happy with this purchase and will be buying more colors in the future.
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    SilverFern
    Lake Worth, US
    ★★★★★ 5
    Good hoodie
    Size: Large, Color: Light Brown
    Was more brown than I thought. But still liked it. Recommend. True to size.
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    MaddDembinski
    Whiting, US
    ★★★★★ 5
    Runs small
    Size: 3T, Color: Black
    Runs just a little small. Maybe upsize, but great otherwise!
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    Reviewed in the United States on February 28, 2026
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    Lorraine
    Lexington, US
    ★★★★★ 5
    I was delighted with the quality and color
    Size: X-Small, Color: Lilac
    This is a super cute, and frankly, fairly high fashion little hoodie. The price was great for what it is. Really nice soft (terry?) inside. Double fabric hood. Really soft. It has an oversized cut which makes it easy to get on and off, but is just the right length to make the sizing look great and intentional - it doesn't look too big. I love the color. It's high quality, and I didn't notice any shrinkage. Even the hood is cut in a chic way. Not your average kids' hoodie.
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    Reviewed in the United States on October 26, 2025

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