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 Aug 13 - Aug 18

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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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4.7 ★★★★★
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Edward Davidson
Chelsea, US
★★★★★ 4
Great ball but poor squeaked design
Size: 4.5"
My Rottie loves these balls. The ball lasts a long time even though he plays hard and chews them. My biggest complaint is the squeaker disconnects easily from inside the ball, the glue does not hold! We have bought many of these balls because eventually the area where the squeaker is attached comes away from the ball leaving an open whole that causes the ball to eventually developed a long crack at which point it no longer is able to be thrown nor is is fun for him any longer.
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Reviewed in the United States on December 19, 2025
A
Verified Purchase
A. Estrella
Natrona Heights, US
★★★★★ 5
Well made and great fun for our Pittie
Size: 4.5"
My pittie loves these! They are way thicker than others. He has learned how to chew on the spikes. Seems like a good teeth cleaning too. Yes, the squeaker breaks! That is a great thing!! With his active chewing, that sound was driving us crazy after a while.
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Reviewed in the United States on February 19, 2026
D
Verified Purchase
Donald
Port Orchard, US
★★★★★ 5
"Durable Fun: Pweituoet Heavy Duty Squeaky Dog Balls for Aggressive Chewers"
Size: 4.5"
Product Review: The Pweituoet 4.5” Heavy Duty Squeaky Dog Balls have been a hit with my dog, proving to be both durable and entertaining. Durability: These dog balls are impressively tough. My dog is an aggressive chewer, and most toys don’t last long, but these balls have held up exceptionally well. The heavy-duty material and spiked design are perfect for dogs who love to chew, providing both durability and safety. Entertainment: The built-in squeaker adds an extra layer of fun. It captures my dog’s attention immediately, and the squeak keeps him engaged for longer play sessions. The spikes also make the ball easy for him to grip and carry around. Size: The 4.5” size is ideal for medium to large dogs. It’s large enough to avoid being a choking hazard but still easy for my dog to pick up and play with. The size and weight are just right for games of fetch, too. Value: Given the durability and how much my dog enjoys these balls, they offer great value for the price. They’ve lasted much longer than other toys we’ve tried, making them a worthwhile investment for any dog owner with a tough chewer. Overall Verdict: The Pweituoet Heavy Duty Squeaky Dog Balls are an excellent choice for medium to large dogs, especially those who are aggressive chewers. They’re durable, fun, and well-sized, making them a great addition to your dog’s toy collection. Highly recommended!
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Reviewed in the United States on August 10, 2024
C
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Chris Wells
Dallas, US
★★★★★ 5
Actually stands up to use
Size: 4.5", Size: 4.5"
I have a pitbull who is a toy destroyer. All those toys, even the ones that say tough enough for destroyers, never hold up. THESE BALLS ARE AWESOME! I bought the 2 pack of the 4.5 inch balls and they lasted a year. I literally am writing this review after ordering a new set. These are well worth the money and Ghost (my dog) loves them. Hes a 103lbs pitbull and his life mission is cuddles and destroying his toys... and these lasting a year of everyday use is friggin awesome. Both toys failed in the same way eventually. They gave out in a circle around the "squeker".
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Reviewed in the United States on September 14, 2024
C
Verified Purchase
CFM
West Palm Beach, US
★★★★★ 3
Neutral
Size: 4.5"
She chewed it up in less than 10 minutes. This is not for heavy chewers but dogs that like to actually play with their toys it would be great!!! I gave it a 3 because it worked for my other dog who likes to play🤘
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Reviewed in the United States on March 8, 2026

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