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Holley EFI 550-929 Terminator X Max Engine Management System LS1/LS6 Drive-By-Wire

Manufacturer

Picture for manufacturer Holley EFI

Part Number

550-929
7 reviews
Sale Price

$1,999.95

In Stock (10+)

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The Holley EFI Terminator X Max (550-929) is a comprehensive standalone engine management system specifically engineered for GM LS1 and LS6 engines equipped with 24x crank reluctor wheels, Drive-By-Wire throttle bodies, and EV1 injectors. This complete plug-and-play system transforms your LS engine with advanced tuning capability and integrated boost control.

Key Features:

  • Real-Time Fuel Map Learning: Automatically adjusts your base fuel table, eliminating guesswork and simplifying the tuning process
  • Advanced Boost Control: Comprehensive boost management with parameters for time, gear, RPM, and speed, plus integrated boost safety features
  • Integrated Nitrous Control: Single-channel wet or dry nitrous control with progressive or non-progressive activation, rich/lean safeties, and target closed-loop AFR
  • Bosch LSU 4.9 Wideband: Precision wideband oxygen sensor provides accurate AFR readings for optimal tuning control
  • Onboard 1-Bar MAP Sensor: Ideal for naturally aspirated or nitrous applications; upgradeable to 2+ bar sensor for forced induction (GM 12592525 with Holley adapter 558-416)
  • 4 Auxiliary Outputs: Ground and PWM-controlled outputs for fans, boost control solenoids, nitrous activation, IAC kits, and other accessories
  • 4 Auxiliary Inputs: 12V, ground, 5V, and frequency inputs for additional sensors, nitrous activation switches, or trans brake triggers
  • Diagnostic LEDs: Onboard status indicators for ECU power, engine run, wideband status, TPS calibration, crank signal, and cam signal allow instant identification of critical issues
  • Compact ECU Design: Small form factor allows flexible mounting locations throughout the vehicle (diagnostic LEDs must face upward)
  • Free EFI Tuning Software: Complete control over every aspect of your engine management with intuitive PC-based software

Included Components:

  • Terminator X Max ECU with integrated wiring harness
  • MAP sensor vacuum hose adapters (1/8" to 1/4" and 3/16")
  • Bosch LSU 4.9 wideband oxygen sensor
  • Complete installation hardware and documentation

Note: Recommended accelerator pedal assembly is GM part number 10379038 (sold separately).

This system delivers professional-grade engine management with the simplicity of a plug-and-play installation, making it the ideal solution for LS1 and LS6 engine swaps, performance builds, and forced induction applications.

Products specifications

Accelerometer Support

Yes

Boost Control

Yes

Brand

Holley EFI

CAN-BUS Support

Yes

Category

Air and Fuel Delivery

Coil Per Cylinder Ignition Support

Yes

Crank Reluctor

24x

Datalogging Support

Yes

Distributor Included

No

Drive-By-Wire

Yes

Dry Nitrous Control

Yes

e85 Support

Yes

EGT Support

Yes

Emission Code

3

Engine

GM LS1/LS2/LS6

Forced Induction Support

Yes

Fuel Filter Included

No

Fuel Hose Included

No

Fuel Injectors Included

No

Fuel Pressure Regulator Included

No

Fuel Pump Included

No

Grade Type

Performance

Handheld Included

Yes

Idle Air Control Motor Included

No

Ignition Timing Control

Yes

Ignition Type

GM LS 24x

Individual Cylinder Fuel Corrections

Yes

Injector Connector

Jetronic/Minitimer (Bosch EV1)

Intake Manifold Included

No

Knock Retard Support

Yes

MAP Sensor

1bar

Mounting Hardware Included

No

Multi-Stage Nitrous Control

Yes

Part Type

Fuel Injection System

Product Type

EFI System

Progressive Nitrous Control

Yes

Self-Tuning

Yes

Sub Category

Fuel Injection System and Related Components

Terminator LS Options

Fuel, Spark, Drive-by-Wire

Throttle Position Sensor Included

No

Transmission

None

User-Tuneable

Yes

Warning

California Proposition 65

Wet Nitrous Control

Yes

First time buyer time will tell

Fair prices , great tires

Fast and easy ordering.

Thnx

I hope it will fit

I found that boatplicity had the best price I could find on the Scotty rod holders and mounts that I needed. I had never ordered from or heard of them before. But I took a chance and placed an order with them anyway because of the lowest price. I was pleasantly surprised! Everything went GREAT!!! I would buy from them again!!! (I do think I should have gotten free shipping on an order that was over $100.00 but I did not.)

Great!!!

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