SKU: 44837067136

Holley Terminator X MAX Engine Management Systems 550-927

Sale price$989.97 Regular price$1099.97
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Description

Holley Terminator X MAX Engine Management Systems 550-927TERMINATOR X MAX MPFI W TRANS & 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

TERMINATOR X MAX MPFI W/TRANS & 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 550-927 also has 4L60E or 4L80E Transmission control and 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:

  • For GM LS 4.8/5.3/6.0 Truck Engines with 24x crank reluctor, Transmission Control, Drive-by Wire throttle body 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-Board Diagnostic LEDS for: ECU Power – Engine Run – Wideband Status – TPS Calibration – Crank Signal –Cam Signal. Allow you to identify any Critical engine issues a
  • 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
  • Recommended Pedal part number - 10379038
  • Includes: 24x LS Engine Main Harness - Multec 2 Injector Harness - DBW Throttle Body 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 ass

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, Drive-by-Wire, Transmission
Part Number 550-927
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: 44837067136

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The Central Scrutinizer
Omaha, US
★★★★★ 5
Worked Great. Save a Near New Tire
Size: 0.16 x 1.42 ,0.24 x 1.77 ,0.35 x 2.36 Inch
I got these because twice this year I picked up a nail in my motorcycle tire. The local shops want to sell tires so they won't patch any tire no matter how new. I used these on two tires, a steel-belted radial and a bias-ply off-road tire. It worked out great, both have been holding air for months now and by doing it myself I saved hundreds of $$$. These are the best way to pemanently patch a tire that's gotten a smallish puncture.
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Reviewed in the United States on December 1, 2025
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Wilson Xu
Massapequa, US
★★★★★ 5
Good quality, Best for schools and shops.
Size: 0.16 x 1.42 ,0.24 x 1.77 ,0.35 x 2.36 Inch
I bought this butyl repair patch and the quality is good. I brought it to the school where I’m learning automotive repair and used it as a teaching consumable. Many students tried it, and everyone thought it worked very well. One thing I would suggest for individual buyers: pay attention to the size combinations in the package. For most car owners, you may end up using only one size more often. Because of that, this mixed-size packaging is probably more suitable for schools, training programs, or auto repair shops where different sizes are needed regularly. Overall, it’s still a good quality product and performs exactly as expected.
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Reviewed in the United States on March 15, 2026
J
Verified Purchase
Jon P Summers
Waukegan, US
★★★★★ 4
Look very useful
Size: 0.16 x 1.42 ,0.24 x 1.77 ,0.35 x 2.36 Inch
Haven't actually used them yet, but they look like the perfect way to fix a flat. As can be seen they come in various sizes depending on what you will need. All you need to get is some tire patch rubber cement and a good inner tire sealer (I picked up a can of Xtra Seal)
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Reviewed in the United States on March 1, 2024
Z
Verified Purchase
Zac Briggs
Belleville, US
★★★★★ 5
Saved me from buying a tire
Size: 0.16 x 1.42 ,0.24 x 1.77 ,0.35 x 2.36 Inch, Size: 0.16 x 1.42 ,0.24 x 1.77 ,0.35 x 2.36 Inch
Took our ancient van on a trip to Florida (from IL) and wouldn't you know we picked up some debris in construction. I was able to plug it however the next morning it was flat again. This time I used 2 plugs to and we were able to get home on that. Realizing this wasn't what I wanted my wife driving around and I didn't wanna buy tires for a van with 250k on it I set out to find some internal patches. I pulled the tire off using a harbor freight bead breaker and some motion pro spoons, used vulcanizing Compound and a dremel and patched it right up. Once the tire is off its a really easy process and I just marked my tire and rim to keep the balance close when it went back together. All appears to be working perfectly with no leaks over the past few weeks. This cost way less than a new tire and now I have more for other holes in the future
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Reviewed in the United States on August 2, 2024
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Verified Purchase
ballpeen
Louisville, US
★★★★★ 5
Better than just a patch
Size: 0.16 x 1.42 ,0.24 x 1.77 ,0.35 x 2.36 Inch
Do what they are suppose to do, easy to use
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 2, 2026

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