SKU: 3089165425

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 15 - Jul 20

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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: 3089165425

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Amazon Customer
Draper, US
★★★★★ 5
Border Collie Approved: Easy to Clean, Durable, and Great Bounce
Size: Medium (2.5"), Style: Fetch Pack 2
These are the best balls out there for dogs. These fit great in the chuck-it ball launcher, which we need to wear out my border collie. They fit her mouth properly and, most importantly, do not absorb all the spit or water after a good rain. They are quick to clean off and have good weight so you can let them fly! Furthermore, they bounce well, which is perfect for my dog that likes to catch them on a bounce. The ball is a strong rubber, so should not be easy to chew up. I've used these for years, and the only time I've had to replace them is when one gets lost in the hay field. I highly suggest these as replacements for the common tennis balls.
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Reviewed in the United States on July 19, 2025
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maxine
Grantham, US
★★★★★ 4
Heavy duty.
Size: Medium (2.5"), Style: Fetch Pack 2
My dog was not interested, but it’s a good product
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Reviewed in the United States on April 11, 2026
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M Denise
Grantham, US
★★★★★ 5
Treats and plenty of ball throwing with these doggie toy
Size: Medium (2.5"), Style: Fetch Pack 1
I have actually purchased these twice already. I love the one that glows in the dark but it still got lost in my yard lol. My dog is a big breed half pitt/Labrador so she did chew through one of them already. I play ball with her every single day but I DO have to take them away from her because she will destroy them. They are great to add in treats as well, that was one of the my favorite things about them as well. They do last just if you have an over zealous chewer do not let them keep them for long periods of time. They are a good value for the price. Buy them your dog will love it!
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Reviewed in the United States on August 2, 2025
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Who Let the Dogs Out
Massapequa, US
★★★★★ 5
My Female GSD loves
Size: Medium (2.5"), Style: Fetch Pack 1, Size: Medium (2.5"), Style: Fetch Pack 1
Shasta is my smallest. Six in December (2025) along with her brother. She’s 100 lbs and outside, completely ball driven see last picture. Don’t let the size (2.5”) of these Chuck-It balls deter you. If your larger Breed dog has any orthopedic issues, has already torn their ACL etc, one has arthritis but wants to play. This size is perfect! Shazzy was born with several ortho issues. I don’t throw balls distance but right to her. This size and lighter weight assure even when Shazzy is spazzy w excitement, she’ll catch the ball mid air. The green balls are softer, and glow in the dark. In summer we can play well past dusk and I can see them! Her personality shows in the pictures. Playing ball is part of her. These balls are just perfect for her situation. Somehow they disappear, she loves making baskets, puts them in my tractor bucket, or my gardening bucket..then get put in burn pile, trash etc. I keep replacing them because she’d look day and night if we actually ran out!! 🙏✝️👍🏼👍🏼
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Reviewed in the United States on September 3, 2025
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Jamie B
Draper, US
★★★★★ 5
Durable , dogs love them !
Size: 2 Count (Pack of 1), Style: Pack of 2, Size: 2 Count (Pack of 1), Style: Pack of 2
These chuck it balls are a fan favorite of my own dogs and my foster pups . So much so I have sent my foster home with them when they go to their new families! I seriously need an endless supply !
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Reviewed in the United States on April 30, 2026

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