Holley EFI 550-931 Terminator X Max ECU System for GM LS Truck and LS2/LS3 Engines

Name: Holley EFI 550-931 Terminator X Max ECU System for GM LS Truck and LS2/LS3 Engines
Brand: Holley EFI
SKU: HBJ-550931
Price: 1999.95 USD
Availability: InStock
Rating: 4.9 (5 reviews)

Manufacturer

Part Number

550-931

5 reviews

Sale Price

$1,999.95

In Stock (10+)

Usually delivered within 2 days

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Show details for Holley EFI 550-931 Terminator X Max ECU System for GM LS Truck and LS2/LS3 Engines

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Holley EFI 550-931 Terminator X Max ECU System for GM LS Truck and LS2/LS3 Engines — image 2

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Holley EFI 550-931 Terminator X Max ECU System for GM LS Truck and LS2/LS3 Engines — image 8

Holley EFI 550-931 Terminator X Max ECU System for GM LS Truck and LS2/LS3 Engines — image 9

Holley EFI 550-931 Terminator X Max ECU System for GM LS Truck and LS2/LS3 Engines — image 10

Holley EFI 550-931 Terminator X Max ECU System for GM LS Truck and LS2/LS3 Engines — image 11

Product Details

The Holley EFI Terminator X Max (550-931) is a comprehensive standalone engine management system designed specifically for Gen IV GM 4.8L, 5.3L, and 6.0L truck engines as well as LS2 and LS3 applications with 58x crank reluctor, 4x cam sensor, and drive-by-wire throttle body using EV6 injectors. This plug-and-play system eliminates the complexity of engine swaps and retrofits with intuitive tuning software and intelligent self-learning capabilities.

Key Features:

Free EFI tuning software with real-time fuel map learning that automatically optimizes your base fuel table
Compact ECU design mounts virtually anywhere (diagnostic LEDs must face upward for visibility)
On-board diagnostic LEDs display critical status at a glance: ECU power, engine run, wideband status, TPS calibration, crank signal, and cam signal
Integrated Bosch LSU 4.9 wideband oxygen sensor for accurate AFR monitoring and precise tuning control
On-board 1-bar MAP sensor ideal for naturally aspirated or nitrous applications (2+ bar sensor upgrade available with GM 12592525 and Holley adapter 558-416)
Advanced boost control with multiple control strategies: boost vs time, boost vs gear, boost vs RPM, boost vs speed, plus built-in safety limits
Nitrous control supporting single wet or dry systems with progressive or non-progressive delivery, rich/lean safeties, and target closed-loop AFR
Four configurable outputs (ground and PWM) for accessories including fans, boost control solenoids, nitrous activation, IAC kits, and more
Four configurable inputs (12V, ground, 5V, and frequency) for additional sensors, nitrous activation switches, trans brake signals, and pressure sensors
Plug-and-play compatibility with Holley EFI accessories including gauges, shift lights, modules, and digital/pro dashes (P/N 553-106, 553-111, 553-112)

System Requirements:

Recommended electronic throttle pedal: GM part number 10379038
Compatible with EV6-style fuel injectors
Requires 58x crank reluctor and 4x cam sensor configuration

The Terminator X Max system provides professional-grade engine management with user-friendly operation, making it ideal for street performance, track applications, and engine swaps where precise fuel and ignition control are essential.

Products specifications

Accelerometer Support

Yes

Boost Control

Yes

Brand

Holley EFI

CAN-BUS Support

Yes

Coil Per Cylinder Ignition Support

Yes

Crank Reluctor

58x

Datalogging Support

Yes

Distributor Included

Drive-By-Wire

Yes

Dry Nitrous Control

Yes

e85 Support

Yes

EGT Support

Yes

Emission Code

Engine

Gen IV GM LS

Forced Induction Support

Yes

Fuel Filter Included

Fuel Hose Included

Fuel Injectors Included

Fuel Pressure Regulator Included

Fuel Pump Included

Grade Type

Performance

Handheld Included

Yes

Idle Air Control Motor Included

Ignition Timing Control

Yes

Ignition Type

GM LS 58x

Individual Cylinder Fuel Corrections

Yes

Injector Connector

USCAR (EV6)

Intake Manifold Included

Knock Retard Support

Yes

MAP Sensor

1bar

Mounting Hardware Included

Multi-Stage Nitrous Control

Yes

Product Type

EFI System

Progressive Nitrous Control

Yes

Self-Tuning

Yes

Terminator LS Options

Fuel, Spark, Drive-by-Wire

Throttle Position Sensor Included

Transmission

None

User-Tuneable

Yes

Warning

California Proposition 65

Wet Nitrous Control

Yes

All good

Melisa R

Fantastic !

Vince E

Only if your product works

Ernest H

Looks nice ! Packaged well.

Robert Kerr J

Received order as promised, packaged well and items were exactly as advertised.

Daniel W

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