Product Summary

Universal Fit, 58x Crank Reluctor, 4x Cam Trigger

  • Specifically designed for GM LS 4.8/5.3/6.0 LS Truck Engines and LS2/LS3 with 58x Crank, 4x Cam and 4L60/4L80E transmissions, and EV6 Injectors
  • The real-time fuel map learn takes the guess work out of tuning your base fuel table
  • Has 4 Inputs for things such as additional pressure sensors, or activation triggers for nitrous activation, or a trans brake
  • Included 3.5" touchscreen handheld controller contains a calibration wizard, that allows you to quickly build a base tune for any LS engine
  • A compact ECU size allows you to mount it virtually anywhere
See more details

Key Specs

MFG. Part #550-918
Ignition TypeFactory GM
Injector ConnectorUSCAR (EV6)
Tuner StyleTouchscreen Handheld
Throttle StyleCable Driven
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Need To Know

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Holley 550-918 Details

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 550-918 also has 4L60 or 4L80 Transmission 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!

  • Designed for GM LS 4.8/5.3/6.0 LS Truck Engines and LS2/LS3 with 58x Crank, 4x Cam and 4L60/4L80E transmissions, and EV6 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 – 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 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
  • Designed for GM LS 4.8/5.3/6.0 LS Truck Engines and LS2/LS3 with 58x Crank, 4x Cam and 4L60/4L80E transmissions, and EV6 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 – 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 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

Application

Designed for GM LS 4.8/5.3/6.0 LS Truck Engines and LS2/LS3 with 58x Crank, 4x Cam and 4L60/4L80E transmissions, and EV6 Injectors.

Specs

**Terminator X ECU's are designed to be mounted with the LED's facing up.

***Designed to work with GM Throttle body P/N's - 12570790, 12580760, and 10379038

Installation Instructions

Handheld & Reference Manual

Wiring Diagram

Holley EFI Support Forums

Terminator X Software

CARB Warning

For race/ off road use or for use on pre-1966 vehicles.

Emissions warning: this part only legal for sale or use in California for racing (competition) vehicles which may never be used, registered, or licensed for use upon a public highway, or if installed in vehicles model-year 1965 or older; motorcycles model-year 1977 or older; or off-highway recreational vehicles (such as off-road motorcycles and all-terrain vehicles) model-year 1996 and older. Any other use renders the vehicle tampered and not legal for use on California public highways (any public street or roadway, public dirt road, public park, or publicly maintained right of way open to the use of the public for vehicular travel). Violations subject to $37,500 penalty per violation per vehicle, revocation of registration, loss of use on California public right of ways, and proof of correction for tampering. There are similar restrictions and penalties under federal law and the laws of all other states with penalties under federal law of up to approximately $45,268 per tampered vehicle and/or engine.

Holley 550-918 Specifications

KEY SPECS
MFG. Part #550-918
BrandHolley
Ignition TypeFactory GM
Injector ConnectorUSCAR (EV6)
Tuner StyleTouchscreen Handheld
Throttle StyleCable Driven
GENERAL
Crank Reluctor58x
Cam Trigger4x
MAP Sensor IncludedYes
Transmission ControlYes
Oxygen Sensor StyleBosch
GTIN Code090127060841
Sold in QuantityKit

Questions & Answers

Fitment

  • GM LS3

  • GM LS3

  • GM LS3

  • GM LS3

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