SKU: 71447637016

Holley Terminator X MAX Engine Management Systems 550-931

Sale price$899.98 Regular price$999.98
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Ships within 48 hours · Estimated delivery Jul 18 - Jul 23

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Description

Holley Terminator X MAX Engine Management Systems 550-931TERMINATOR X MAX MPFI W DBW 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

TERMINATOR X MAX MPFI W/DBW

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 550-931 also has Drive-By Wire Throttle Body 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 4.8/5.3/6.0 LS Truck Engines and LS2/LS3 with 58x Crank, 4x Cam and a Drive-By-Wire Throttle Body, with 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 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.
  • 4 Outputs – Ground, PWM - , for accessories such as; fans, boost control, nitrous control, IAC Kit, and More
  • 4 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
  • 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
  • Recommended Pedal part number - 10379038
  • Includes: 58x/4x LS Engine Main Harness - EV6 Injector Harness - DBW Throttle Body 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, Drive-by-Wire
Part Number 550-931
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: 71447637016

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Verified Purchase
Tina Taylor
Fort Morgan, US
★★★★★ 3
Ok
Ok
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 6, 2026
J
Verified Purchase
J. Rogers
San Leandro, US
★★★★★ 5
This is a great ball for high energy dogs.
Color: Blue
I have a Belgian Malinois, so you can imagine the Maligator jaws. Just opened this today and let her play with it indoors. She LOVES IT. It wore her out and it’s a toy she can really stay focused on without needing me to throw or roll for her. It moves on its own! I supervised her play. I was hoping it was too big to get under the couch, but no. It goes right under it. I had to block off the gap so I didn’t have to keep getting it out from under for her. The outter “shell” is very durable! When she had resting moments, she chewed it pretty good - I could hear the material squeaking against her teeth. I was worried she was tearing it up, but nope! Not a mark on it. It’s easy to set up and operate. It needed charging before play. After hours of play, she was able to somehow unscrew the outter shell. This concerned me bc the smaller, inner ball mechanism came out but I saw it right away and was able to put it back together. So, make sure it’s screwed together tightly (which I thought I had done without breaking it) and check it from time to time to make sure it hasn’t loosened. This is a great ball for her incredible high energy drive. It gives her the work and fun play she needs to get tired, which I love. This toy is on the expensive end, but so far it’s worth it. Now we’ll see how long it lasts!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 7, 2025
C
Verified Purchase
Carol D
Phoenix, US
★★★★★ 5
Love love it
Color: Blue
Best dog toy ever. I have a 1 year old boxer who is full of energy (understatement). This ball has provided more entertainment for us both than any dog toy I’ve ever purchased. Charge holds well and has a very resilient shell. I love it. Worth the price.
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Reviewed in the United States on May 23, 2026
M
Verified Purchase
Megan
Lowell, US
★★★★★ 4
Great ball for limited entertainment. Replaceable outer shell is an amazing option!
Color: Blue, Color: Blue
Bought this for our 45lb, ball-obsessed Dutch shepherd/pit bull dog mix. I had one of these years ago with the hard shell and couldn’t be happier with the new foam shell. The new foam shell is much quieter and while our dog might put holes in it with his teeth, he doesn’t seem to ever pull pieces off. For engagement level, he found it VERY interesting at first and was scared to grab it, but once he got over that he started holding it in his mouth even when it shakes and just tries to keep it. Isn’t the best for fetch or anything as he has trouble letting it go when it is actively moving, but it makes him happy while he has it. We just make sure to monitor him while it is out. The ability to change the outer shell and just buy a replacement for the shell instead of a whole new toy is a lovely feature that makes me very happy to continue buying from this company.
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Reviewed in the United States on April 19, 2026
A
Verified Purchase
April L Patrick
Cuba, US
★★★★★ 5
Great Interactive Option
Color: Blue
To start, I have been very happy with this purchase. A couple of key points for me are durability and being able to keep my dog's attention. I have had it for almost a year, just a month shy, and she hasn't managed to get through the foam outer shell even though she tries real hard to do so. Let's just say, she's hard to find toys for because of her habit of finding the point of failure where she can pick and gnaw at until the toy is no longer safe for her to have. With this toy, she not only found her match, but it also has her watching, waiting, and even stalking. Only one small issue has recently occurred: the motor has started having an issue where the charge doesn't hold, and it doesn't remain on afterwards. I have reached out to Cheerble directly to see about replacing it since I am still within their 12-month timeframe, and they responded right away.
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Reviewed in the United States on April 22, 2026

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