SKU: 26895536892

Holley Terminator X MAX Engine Management Systems 550-929

Sale price$899.98 Regular price$999.98
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Ships within 48 hours · Estimated delivery Aug 1 - Aug 6

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Description

Holley Terminator X MAX Engine Management Systems 550-929Take 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

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 550-929 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:

  • For GM LS1/LS6 engines with 24x crank reluctor and a Drive-By-Wire Throttle Body, and EV1 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
  • Recommended Pedal part number - 10379038
  • Includes: 24x LS Engine Main Harness - EV1 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 24x
Emission Code 3
Ignition Type GM LS 24x
Injector Connector Jetronic / Minitimer (Bosch)
Product Type Terminator X Max LS MPFI
Terminator LS Options Fuel, Spark, Drive-by-Wire
Part Number 550-929
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: 26895536892

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The Southwest Grasshopper
Whiting, US
★★★★★ 5
Good replacement parts and affordable
I acquired this filter set to replace the OEM filters in my wife's Honda Accord. The filters fit perfect and were easy to install. Normally when I replace filters I have to purchase both the air filter and the cabin filter separately. In this case, it was very nice to have them sold as a combo set. While I don't know what materials are used to manufacture these filters, I will say that the air filter looks just like the OEM part in terms of it's production. The cabin filter does have carbon built in to help control orders, which is something the OEM part did  not have, so it looks different in terms of filter color. I normally replace filters every 10K to 15K miles, and this fits in line with that this manufacturer suggests (every 12K miles).  In all, a decent combo set of filters helps keep costs down and both filters can be replaced at the same time. 
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Reviewed in the United States on July 6, 2025
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K Alex
Louisville, US
★★★★★ 5
Perfect!!!
This is exactly what I needed. Fits perfectly for my 2018 Honda Accord as well as being very easy to install. This is coming from someone who has no idea about doing anything on my car. Provides the best function, just as it would coming from a dealer or other auto shop. The quality is great as well, and this is exceptional value for the money. If you are looking to save money and not get bombarded with the filter replacement question when getting an oil change then this is the one for you.
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Reviewed in the United States on August 4, 2025
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T. Isaacson
Carnegie, US
★★★★★ 5
Fit is good.
Filters fit and look essentially the same as the filters I’ve purchased and the official types from the dealer. I live in an area where wildfires occur almost every year,  so it’s good to have an extra set of filters to change them out after a run of smoky days. 
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Reviewed in the United States on July 1, 2025
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Charles
Lake Worth, US
★★★★★ 5
Priced affordable, easy installation, fits snug and perfect and seems durable!!
This cabin air filter and engine air filter seems to be made of high quality materials, installation was a breeze, fitment seems to be perfectly snug affordably priced for a cabin air filter and an engine air filter combined, as for functionality, Only time will tell on its durability.
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Reviewed in the United States on July 2, 2025
A
Verified Purchase
AK
San Leandro, US
★★★★★ 5
cabin air for 4th gen runner
fit perfectly in my 4th gen runner, mine was original if you can believe it, (2003) and needed HELP.. dont think just click the purchase button and enjoy fresh breathable air again.
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