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 Aug 2 - Aug 7

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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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IT Secure Force
Lowell, US
★★★★★ 5
Excellent dog balls — safe design and very durable
Style: Fetch Balls (Pack of 3), Size: 2.5 inch
These fetch balls from Amazon Basics are fantastic, and my dog absolutely loves them. One of the biggest reasons I prefer these over other brands is the hole that runs through the center of the ball. This is a very important safety feature: if a dog were to accidentally get the ball stuck in the back of the throat, the hole allows air to pass through. That small detail could literally make a life-saving difference. Aside from the safety benefit, they bounce well, are easy to clean, and hold up to a lot of playtime. They’re firm but not rock-hard, and my dog goes crazy for them. Great value, great quality, and a thoughtful design. Highly recommended for dog owners who want a safer alternative to standard solid rubber balls.
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Reviewed in the United States on December 1, 2025
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mike
Chelsea, US
★★★★★ 5
Great ball for heavy chewers
Style: Assorted Balls (Pack of 3), Size: 2.5 inch
Great toy for my Doberman. She chews through tennis balls in about 15 minutes but these are very durable. She likes to chase them but also just chew on them.
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Reviewed in the United States on April 26, 2026
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Me
Houston, US
★★★★★ 5
Durable
Style: Fetch Balls (Pack of 2), Size: 3 inch
Very bouncy. I like the noise it makes when you throw it. Pretty durable. Good size. Dog loves to play with them. Good material. Easy to use.
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Reviewed in the United States on April 5, 2026
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Susan Cedar
Omaha, US
★★★★★ 4
My dog loves glowing fetch at night!
Style: Glow Balls (Pack of 3), Size: 2.5 inch
Fantastic. Sturdy. My dog loves them Glow in the dark is great for fetch at night. I keep a flashlight with me because the glow doesn't last really long. But they charge very quickly and are really bright.
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Reviewed in the United States on February 22, 2026
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Maddox
Houston, US
★★★★★ 5
Indestructible
Style: Fetch Balls (Pack of 2), Size: 3 inch
These balls are indestructible! We have a lab and a lab mix and they CANNOT damage these balls. They love them for fetch and to just chew on them (slightly squishy, but NO damage). Best toys we have bought for them.
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Reviewed in the United States on April 19, 2026

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