SKU: 39296231040

Holley Terminator X Engine Management Systems 550-905

Sale price$719.98 Regular price$799.98
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Ships within 48 hours · Estimated delivery Jul 14 - Jul 19

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Description

Holley Terminator X Engine Management Systems 550-905TERMINATOR X MPFI, LS2 LS3 & LATE TRUCK Take control of your LS engine with Terminator X! 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 features real time fuel learn, high impedance injector drivers, an integrated 1bar MAP sensor, and 4 programmable inputs

TERMINATOR X MPFI, LS2/LS3 & LATE TRUCK

Take control of your LS engine with Terminator X! 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 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. Terminator X 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 has the features and technology you need at a price that won't break the bank!

Features:

  • Designed for GM LS Engines with 58x Crank, 4x Cam - 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 systems utilize the Bosch LSU 4.9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control.
  • 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
  • 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
  • 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!adjustable through included 3.5” f
  • 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 - Terminator X 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 LS MPFI
Terminator LS Options Fuel, Spark
Part Number 550-905
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: 39296231040

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Sarah Sofía Ortiz Campos
Cuba, US
★★★★★ 1
No recomiendo
Format: Paperback
Muy malo, no vine completo, además se demoró mucho más de lo que decía al momento de comprarlo. Solo aplazaban la fecha de entrega sin consultar cómo afectaba al cliente. Yo tuve que presentar el examen sin el libro, porque no llegó en la fecha que decía al comprarlo y después se cambió 3 veces la fecha, casi cumpliendo el mes.
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Reviewed in the United States on December 30, 2025
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Elaine li
Pawtucket, US
★★★★★ 5
VERY EFFICIENT MATERIAL
Format: Paperback
It's the most efficient material to prepare the test.
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Reviewed in the United States on April 1, 2020
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ThereseHazzard
Lexington, US
★★★★★ 5
All around helpful---worth the money!
Format: Paperback
This guide has been most helpful for all the folks I help prepare for the iTEP test! It gives insight into what each section of the test is looking for along with examples and great tips about actually TAKING the test. In the Writing and Speaking sections, it also gives sample scores and comments from the Master Grader which is very helpful too.
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Reviewed in the United States on August 9, 2019
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Thomas J. Shandorf
Lowell, US
★★★★★ 5
Comprehensive, clear and coherent!
Format: Paperback
The iTEP Practice Guide combines a no-nonsense approach to the specific iTEP tests and at the same time offers exercises that task the student with what they need to know. Exercises not only serve the purpose of scoring well, but the overall approach is communicative competence. We use the text in our group and one-to-one classes with very positive--and lasting--results.
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Reviewed in the United States on July 23, 2019
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Sarah Sofía Ortiz Campos
Pawtucket, US
★★★★★ 1
No recomiendo
Format: Paperback
Muy malo, no vine completo, además se demoró mucho más de lo que decía al momento de comprarlo. Solo aplazaban la fecha de entrega sin consultar cómo afectaba al cliente. Yo tuve que presentar el examen sin el libro, porque no llegó en la fecha que decía al comprarlo y después se cambió 3 veces la fecha, casi cumpliendo el mes.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 30, 2025

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