SKU: 24624391210

Holley 550-926 EFI Terminator X Max - LS1/LS6

Sale price$966.60 Regular price$1074.00
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Description

Holley 550-926 EFI Terminator X Max - LS1/LS624x Crank 1x Cam EV1 Injectors Drive By Wire Throttle Body and Transmission Control 3. 5 in. Touchscreen Part Number: 550 926 Take control of your LS engine with Terminator X Max! 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 Max features real time fuel

24x Crank - 1x Cam - EV1 Injectors - Drive-By-Wire Throttle Body and Transmission Control - 3.5 in. Touchscreen

Part Number: 550-926

Take control of your LS engine with Terminator X Max! 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 Max 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. Part number 550-926 also has 4L60E or 4L80E Transmission control and Drive-By Wire Throttle Body control. Terminator X Max 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 MAX has the features and technology you need at a price that won't break the bank!

Features and Benefits

• For GM LS1/LS6 engines with 24x crank reluctor with EV1 injectors and 4L60E/4L80E transmissions, and drive-by wire throttle body control.
• 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 Max systems utilize the Bosch LSU 4.9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control.
• On-Board 1bar MAP sensor, is perfect for N/A or Nitrous engine combos. If your combination requires a 2+Bar, we recommend GM 12592525, and our adapter part number 558-416.
• 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
• 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!
• 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
• 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 multiple Holley EFI accessories including our gauges, shift lights, various modules, and digital and pro dashes (Holley P/N's 553-106, 553-111, and 553-112)
• Free EFI Tuning Software for complete control of your Terminator X power plant
• Recommended Pedal part number - 10379038
• Includes: 24x LS Engine Main Harness - EV1 Injector Harness - DBW Throttle Body Harness - 4L60E/4L80E Transmission Control Harness - Terminator X MAX ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - I/O Harness

Not recommended for 4x4 applications with electronic transfer cases. Not compatible with 4L6X transmissions from model year 1995 or before due to year-by-year changes in converter lockup and downshift strategy. ECU is not recommended for marine applications, but can be used on off-road applications as long as you choose a safe location, keep it dry, protect from heat, and ensure proper wiring management.
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: 24624391210

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4.2 ★★★★★
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Amazon Customer
Cuba, US
★★★★★ 5
Great boys slim fit suit for weddings, church, or special events
Color: Medium Grey, Size: 12
Great kids suit. Comes with a jacket, pants, and tie. Does not have a shirt. Fits as expected. Classic cut on the lapels. Great quality materials. Well made pants and jacket. The color is consistent without any fade or dark spots that can happen with lower quality fabrics. Looks great on. My son loves it. Says it is not restrictive, he can move easily in it. Highly recommend for church, special events, weddings, etc.
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Reviewed in the United States on October 22, 2025
M
Mommynificent
Grantham, US
★★★★★ 5
Nice high-quality, light weight suit for a tween!
Color: Navy Blue, Size: 10
This is such an attractive suit for a tween boy! My son loves dressing up, and this is his new favorite suit. He really likes the double-breasted style and the light weight of the fabric so that it isn't too hot. The tie that came with it gives major Harry Potter vibes which we weren't expecting, but he has lots of other ties that he also enjoys pairing with it. The size seems right, and it fits him well. He says it is very comfortable. I'm happy with the quality and the navy color.
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Reviewed in the United States on October 14, 2025
A
A. Beauto
Dallas, US
★★★★★ 5
Stylish and great value!
Color: Medium Grey, Size: 14
This grey suit was a great find for a school ceremony and will definitely be used again. The neutral color makes it easy to pair with different shirts and ties, and it has a modern, clean-cut look. The jacket and pants fit nicely after a quick press, and the quality was better than I expected for the price. It lost a star only because the waist on the pants needed a slight adjustment, but overall, we’re very happy with it!
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Reviewed in the United States on October 10, 2025
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N. Hale
Natrona Heights, US
★★★★★ 3
Runs big, and fabric may not be same color as picture
Color: Medium Grey, Size: 16, Color: Medium Grey, Size: 16
This suit was a good find for us, as we usually dress up for church, and my 13 yo son often wears suits. He normally wears a size 16, so that’s what we ordered, and in dark charcoal gray. The suit we got was a light, heathered gray that didn’t look much like the one in the picture. It was very wrinkly and thin, and a little scratchy. Also, the sleeves were way too long and the torso cut of the jacket was pretty wide. The pants were very large in the waist, but fit him decently in the length (he’s 5’4” and weighs 90 lbs). Overall the suit looked like it was drowning him, so I would order a size down unless you have a larger child/teen. Because of the ill fit, I haven’t had the chance to see what the suit looks like on him as it’s supposed to, but I guess I’ll return it or wait a year or two until he fills it out a bit more. Not overly impressed with the quality, so I’m not sure I’d pay $55 for this one again.
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Reviewed in the United States on October 20, 2025
A
Amy
Lexington, US
★★★★★ 5
Adorable, Complete Set—Great for Special Occasions
Color: Beige, Size: 12, Color: Beige, Size: 12
This suit set is such a great find! It comes with everything you need—jacket, pants, shirt, tie, and bow tie—which makes getting a dressed-up look so easy. It's excellent quality for a suit in this price range. The linen fabric gives it a nice, lightweight feel and a polished look that works well for both formal and semi-casual events. My son looked adorable in it, and it was perfect for the spring wedding we attended. What I love: Complete 5-piece set—no need to buy extras Lightweight and comfortable material Classic, stylish look with nice details (lapel, pockets, etc.) Adjustable waistband is super helpful for fit Versatile for weddings, holidays, and other events Fit was true to size based on the chart, but I agree with the recommendation—if your child is between sizes or growing quickly, sizing up is a good idea. I sized up with the hopes that he can wear it again for another event because it looks fantastic! Overall, a really cute and practical suit set that looks great without being uncomfortable. Perfect for any special event
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Reviewed in the United States on April 22, 2026

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