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- USA
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Ships within 48 hours · Estimated delivery Jul 10 - Jul 15
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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
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★★★★★ 5
Recommend
Material Type: Recycled Polyester, Color: Dark Navy, Size: X-Large
Great fit, right price
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Reviewed in the United States on March 18, 2026
★★★★★ 5
Nice polo
Material Type: Recycled Polyester, Color: Dark Teal, Size: Medium
Fantastic polo shirt. Size was true to fit. Color is amazing. It’s soft and it has held up through washes since Christmas.
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Reviewed in the United States on March 14, 2026
★★★★★ 5
Great shirt for the price.
Material Type: Recycled Polyester, Color: Electric Blue, Size: Large
Bought this for my son. Very nice shirt for the price, it is true to size and the color is the same as the picture. Would definitely buy it again. The material is good quality. No issues whatsoever
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Reviewed in the United States on May 19, 2026
★★★★★ 5
Great purchase
Material Type: Recycled Polyester, Color: Dark Navy, Size: X-Large
Purchased several shirts, all were great quality. You never know what you’ll get when you purchase sight unseen, these are worth it. Great value, style, and comfort. Color is exactly what you see online. True to size.
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Reviewed in the United States on November 25, 2025
★★★★★ 4
Great quality for price
Material Type: Recycled Polyester, Color: Red Stripe, Size: XX-Large
Very impressed with the shirt quality, especially for such a low price. Sizing is accurate.
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Reviewed in the United States on May 21, 2026