SKU: 38192262630

Holley EFI Terminator X Max - LS1/LS6 550-929

Sale price$865.78 Regular price$961.98
Save 10%

Pay in installments of $240.50 with ShopPay, AfterPay and Klarna

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Sep 19 - Sep 24

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

Description

Holley EFI Terminator X Max - LS1/LS6 550-929Take 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

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 550-929 also has 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:

  • For GM LS1/LS6 engines with 24x crank reluctor and a Drive-By-Wire Throttle Body, and EV1 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 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 Ð _ and 3/16ths)
  • 4 Inputs Ð 12v, Ground, 5v, and Frequency, for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
  • 4 Outputs Ð Ground, PWM - , for accessories such as; fans, boost control, nitrous control, IAC Kit, and More
  • Boost Control Ð Boost vs Time, Boost vs Gear, Boost vs RPM, Boost vs Speed, Boost Safeties
  • Nitrous Control Ð Single Channel of Wet or Dry, Progressive or Non-Progressive, Rich/Lean Safeties, and target Closed Loop AFR
  • Advanced Tables Ð 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 Ð Engine Run Ð Wideband Status Ð TPS Calibration Ð Crank Signal ÐCam 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 - Terminator X MAX ECU - ECU Main Power Harness - Bosch LSU 4.9 Wideband Oxygen Sensor - Input/Output Harness - and assorted vacuum adapters.

About Holley EFI

Find standalone EFI for LS, Coyote, Hemi and more at Holley.com. From engine swapping to managing up to 4000 horsepower, we have a solution for every project!

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: 38192262630

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.8 ★★★★★
Based on 26 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
R
Verified Purchase
Rene Bechard
Fort Morgan, US
★★★★★ 5
LOVE IT !
Size: Queen (Mid Loft), Number of Items: 1
I love this pillow. It is just right, firm enough yet soft. My head sinks in and is very comfortable. When I lift my head, the pillow bounces right back into shape. If it lasts, I will buy my family each a pillow as it is wonderful. I woke up with zero neck pain as I typically did when using a standard foam pillow. There is a very light scent yet when I covered the pillow with a protector casing and then a cotton case, there was zero scent. I highly recommend. Especially when compared to the comfort of a very expensive latex pillow my husband uses.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 7, 2026
I
Verified Purchase
I'maGryffindor
Port Orchard, US
★★★★★ 5
Memory foam could never
Size: Queen (Mid Loft), Number of Items: 1
Wonderfully firm, yet responsive and lightweight. Like a marshmallow for your head and neck. I'm a side sleeper, but this could be great for anyone needing firm but still very soft and comfortable support. Memory foam has nothing on actual latex.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 5, 2026
J
Verified Purchase
Just a guy
Port Orchard, US
★★★★★ 5
Awesome pillow!
Size: Queen (Mid Loft), Number of Items: 1
Great pillow! I have two latex pillows now and I don't think I'll ever go back to standard pillows.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 27, 2026
R
Verified Purchase
Rachel c.
Grantham, US
★★★★★ 5
Expensive
Size: Queen (Mid Loft), Number of Items: 1
Very comfortable, smell goes away
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 21, 2026
L
Verified Purchase
Lisa R.
Pawtucket, US
★★★★★ 5
Winners in my book
Size: Queen (Mid Loft), Number of Items: 1
Great bang for your buck ! Almost have a bunch feel to them. Hold their shape
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 29, 2026

recommand products