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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 550-904TERMINATOR X MPFI, 4. 8 6. 0 EARLY 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, 4.8-6.0 EARLY 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:
- For GM LS Engines with 24x crank reluctor and Multec 2 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 Outputs – Ground, PWM - , for accessories such as; fans, boost control, nitrous control, IAC Kit, and More
- 4 Inputs – 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
- 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: 24x LS Engine Main Harness - Multec 2 Injector Harness - Terminator X ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - Input/Output Harness - and assorted vacuum adapters.
Application
- 2003 - 2006 Chevrolet Express
- 2003 - 2006 GMC Savana
- 1999 - 2006 Chevrolet Silverado
- 1999 - 2006 GMC Sierra 1500
- 2000 - 2006 Chevrolet Tahoe
- 2000 - 2006 GMC Yukon
- 2002 - 2007 Chevrolet Avalanche
- 2002 - 2006 GMC Yukon XL 1500
- 2003 - 2005 Chevrolet TrailBlazer EXT
- 2003 - 2004 Isuzu Ascender
- 2003 - 2004 GMC Envoy XL
- 2003 - 2004 Chevrolet SSR
- 2004 Buick Rainier
- 2002 - 2007 Chevrolet Silverado 1500
Specs
| Brand | Holley EFI |
|---|---|
| Crank Reluctor | 24x |
| Emission Code | 3 |
| Ignition Type | GM LS 24x |
| Injector Connector | Multec 2 |
| Product Type | Terminator X LS MPFI |
| Terminator LS Options | Fuel, Spark |
| Part Number | 550-904 |
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- 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
4.6 ★★★★★
Based on 1833 reviews
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Product Reviews
★★★★★ 5
Great For Battery Chargers On a Shelf!
Love this power strip, had it for probably a year plus now abs works great! The sole reason I purchased this item was so I can select what stays on and what gets turned off. I have this in my utility room and the sole purpose is to plug in battery chargers and to be able to turn off those battery chargers and leave the charger sitting there with the battery in the charger with no power. There is a light that tells you when a product is on and when a product is off . Example: I have AA&AAA battery charger, Ryobi leaf blower charger, Ryobi edger charger and any other charger I want. I have a night light plugged into it because angle allows that. The strip also has a USB that I use for a rechargeable Dremel used for dog nails or toy could use it for cell phone etc. My Flying Pig Grooming Dryer is attached and used with this strip as well. I have had no tripping issues with this power strip but I do keep in mind one high power items such as my grooming dryer at a time.
I have a different company's power strip in my room just for you ladies it hidden behind a mirror and you can keep all your appliances plugged in and cell phones with the option of turning them all off with a button, cutting off power. This is an easy to reach power cord great for putting on a shelf. I am not sure how well it would work behind furniture due to the angle of the plugs. This worked with no issues and I would recommend this and purchase again. Now I am not concerned about saving items due to power surges with this power strip, I have strips that cost a lot of money a lifetime guarantee for those high end electronics like computers TV sets Etc
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Reviewed in the United States on January 18, 2026
★★★★★ 5
Good setup
This has been super useful and functional, I recommend it as it’s a nice way to keep your setup organized, I enjoy having the on and off switches go each outlet, only call out would be the buttons light up when on to show they are on and they are quite bright, so take note of it, it catches me off guard sometimes when I forget they light up and I turn my lights off, but it’s easier to keep in mind what I have charging. The speed of charging is good, the amount of plugs is a fair amount, I plug in my head phones, phone, watch, power bank and monitor. Then there’s the two usb as well as 2 usbc ports, it’s very convenient. It held up well it’s definitely good quality.
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Reviewed in the United States on March 22, 2026
★★★★★ 5
Thoroughly enjoy this product and will purchase again
I purchased two of these at different times.
I really like this item. I like the idea that I could shut off some of the switches that I really don’t need. I have one set up in the guest room for when we have company they can turn on whatever plugs they need. I’ll always have alarm clocks lamps telephone jacks hooked up, but all the switches are turned off so it doesn’t waste electricity. (that’s my theory anyway.) I purchased a second one to go beside my chair in my living room I don’t need that many outlets at all times but occasionally I do and I enjoy again like having the opportunity to shut off any outlets that I’m not needing at the time it seems to me it’s a good power saver and I do like the USB ports everything fits and it’s perfectly organized and it’s great quality surge protector and durability. I hope this review assist you in anyway and I will probably come back and purchase a third one for another room once I get that room cleaned out Truth Hurts on it, but that was my testimony..
This is my honest review in my opinion I hope it’s able to help you make your decision. I personally don’t think you would go wrong but I don’t know what you’re plugging into the outlet so I think that makes a bit different. I just use it for lamps and telephone jacks or small items I don’t use anything. It pulls a lot of voltage. .
Y’all take care of yourselves be kind to one another and go see your parents or your grandparents or a family member if anything else pick up the phone and tell them hello and you were thinking about
Let’s spread love, not hate
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Reviewed in the United States on February 28, 2026
★★★★★ 5
Has a ton of quality of life features!
These are one of those products that makes you go "why doesn't anyone else do this"?
First off, the 45 degree(ish) angle that the outlets are at. Since a lot of outlet adapter plugs can be plugged in upside down, the angle of the outlet helps considerably for semi-tight spaces. While also still having room to turn the individual outlets on and off. The width spacing is also considerably large so those beefy power bricks won't overlap/block-off other outlets.
Secondly, the prior-mentioned outlet on and off switches. Each individual AC outlet has its own on/off switch. So if I have a lamp that always needs to be plugged in, I can leave that on.
If I have a USB C adapter brick to charge my phone, I can turn that off when its not in use. Without needing to turn off the lamp's outlet in the process.
Thirdly, the always on USB A (the rectangular USB outlets), and the USB C ports to the top side of the outlet. Please note that the USB C ports are about 20 watts. So while it can TECHNICALLY charge a laptop, its best used to passively charge a laptop when it isn't being used. Not while actively using a laptop. Since even moderately efficient laptops can draw watts well into the 40's range.
That aside, when used within their intended watt ranges, they're extremely convenient to have in addition to everything else.
I generally use them to charge things like power banks. Possibly low powered USB C devices like a Nintendo Switch or even a GPD microPC which draws 15 or so watts while in use.
So while the ports aren't the highest in terms of watts, there's times of many where I didn't care how many watts a port had, I just needed a USB port period.
Fourth wise, the safety protections. If you somehow manage to overload this outlet, it can cut off its own power. It can be "reset" by pressing the red button to the side.
Fifthly, the actual plug to plug the power outlet into a wall or in my case a UPS machine, is insanely flat. With the cord being at a 45 or so degree angle. So even if its on a top outlet, it probably won't block off most plugs from using the bottom outlet.
Sixth and finally (at least from what I remember off the top of my head 😂), the wire that connects the power outlet to your power source is really flat and easy to manage.
All of these traits makes it one of the least contentious things anybody can buy. Its just a straight up quality of life improvement. If I ever need more power outlets, I know which one to double dip on!
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Reviewed in the United States on October 29, 2023
★★★★★ 4
Skin
Good power cord with multiple functions.
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Reviewed in the United States on June 8, 2025