SKU: 67777550402

Holley Terminator X Engine Management Systems 550-904

Sale price$719.98 Regular price$799.98
Save 10%

Pay in installments of $200.00 with ShopPay, AfterPay and Klarna

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Aug 14 - Aug 19

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

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:
  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: 67777550402

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.5 ★★★★★
Based on 27 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
L
Verified Purchase
LSK
Waukegan, US
★★★★★ 5
No White Cast
Size: 1.7 Fl Oz (Pack of 1)
No white cast. I use the 2 finger method and have medium-deep skin tone. I have slightly oily skin and it does not leave my skin with a greasy, shiny or sticky either. I will definitely buy this again.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 6, 2026
H
Verified Purchase
Haakon
Chelsea, US
★★★★★ 5
Best sunscreen in the market
Size: 1.7 Fl Oz (Pack of 1)
Very good quality sunscreen. Doesn't cause break outs. Good for sensitive skin. Invisible and blends into skin well but does leave a slight white dew to your face. This is okay with me though
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on September 26, 2025
A
Verified Purchase
Alan
Houston, US
★★★★★ 5
Good sunscreen
Size: 1.7 Fl Oz (Pack of 1)
It protects pretty good and stays for a long period of time. Keeps skin hydrated!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 5, 2026
T
Verified Purchase
TM
Pawtucket, US
★★★★★ 5
Lightweight, Protective and Perfect for Everyday Use
Sun protection factor: 50 Sun Protection Factor (SPF), Size: 8 Fl Oz (Pack of 1)
Hawaiian Tropic Everyday Active SPF 50 sunscreen has quickly become my go-to for daily sun protection. The lotion feels light and non-greasy on the skin, which makes it easy to apply and absorb. There is no sticky residue or heavy feeling at all. I love that it’s broad-spectrum and water-resistant so I feel confident that it’s protecting me during outdoor activities, whether I’m at the beach, hiking or just running errands. Plus, being oxybenzone-free is a huge bonus for anyone mindful of ingredients. The scent is subtle and pleasant while not being overpowering like some sunscreens and the 8 fl oz size is perfect for keeping at home or in my bag. Overall, it’s effective, easy to use and keeps my skin safe and hydrated. Highly recommend for daily sun protection!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 3, 2025
M
Verified Purchase
Maggie
Lexington, US
★★★★★ 5
Lightweight and Smells Amazing
Sun protection factor: 50 Sun Protection Factor (SPF), Size: 8 Fl Oz (Pack of 1)
I was really impressed with how lightweight this sunscreen feels on the skin. It absorbs quickly and does not leave a greasy or heavy feeling behind. The scent is honestly one of my favorite parts because it smells so good and reminds me of being on vacation. I only used it on my body and not my face, and it worked perfectly for everyday sun protection. Overall it is such an easy, pleasant sunscreen to wear and I would definitely buy it again.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 5, 2025

recommand products