SKU: 60125247095

Holley Terminator X MAX Engine Management Systems 550-919

Sale price$899.98 Regular price$999.98
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Description

Holley Terminator X MAX Engine Management Systems 550-919TERMINATOR X MAX MPFI W TRANS, LS1 W EV6 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, LS1 W/EV6

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 550-916 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 LS1/LS6 engines with 24x crank reluctor with EV6 injectors and 4L60E/4L80E transmissions
  • 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: 24x 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 24x
Emission Code 3
Ignition Type GM LS 24x
Injector Connector USCAR (EV6)
Product Type Terminator X Max LS MPFI
Terminator LS Options Fuel, Spark, Transmission
Part Number 550-919
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: 60125247095

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J
Verified Purchase
Jennifer
Battle Creek, US
★★★★★ 4
Long lasting
Color: Dogwood & Calming, Size: Medium
My dogs love these bones.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 25, 2026
K
Verified Purchase
Kelli Thornburg
Chelsea, US
★★★★★ 5
Puppy loves these sticks!
Color: Dogwood & Calming, Size: Medium
Dogs love these sticks! Must smell and taste like real wood because it keeps my puppy from bringing real sticks in the house from outside. She is a heavy chewer and these sticks keep her occupied. We are on our 2nd set.
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Reviewed in the United States on May 27, 2026
C
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C. H.
Boise, US
★★★★★ 5
Great value for the price, highly recommend
Color: Dogwood & Calming, Size: Medium
Our dog loves these and chews them down to nothing. They are a great value for the money and the use your dog gets out of them. The size is just right for our doberdor.
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Reviewed in the United States on May 20, 2026
L
Verified Purchase
LC
Phoenix, US
★★★★★ 3
Our dog loves it but it wasn’t durable enough to last
Color: Dogwood Jack, Size: Large, Color: Dogwood Jack, Size: Large
Our lab took to it as soon as we gave it to her. Perfect size for our 80 lb yellow lab. However, now that it’s in about 10 days, she’s able to break off chunks from this bone that are dime size or larger, and we have to throw it away
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Reviewed in the United States on May 1, 2026
M
Verified Purchase
Matthew Anderson
Natrona Heights, US
★★★★★ 5
No problems after a year and a half
Color: Dogwood & Calming, Size: Medium
Have been regularly buying these for my corgi for about a year and a half. The 2 pack lasts about a month or 2 each time. Pieces break off in small enough pieces that they safely pass through his digestive system. He gnaws each one down to about 1/4 the original size before we take it away and give him a new one. He continues to have regular bowel movements and has a healthy appetite so I can’t imagine any problems arising after so long. I have tried other alternatives and every other similar chew breaks off in larger pieces and didn’t feel comfortable letting him chew/eat them. I noticed there are a few 1 star reviews saying their dogs got sick off these but after a year and a half I have had 0 issues with this product. I guess it depends on the dog and how big of pieces they are swallowing. My dog ingests pieces about the size of a grain of rice so just pay attention and you should be fine.
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Reviewed in the United States on February 18, 2026

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