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Holley EFI 550-916 Terminator X Max Engine Management System LS1/LS6 with Transmission Control

Manufacturer

Picture for manufacturer Holley EFI

Part Number

550-916
5 reviews
Sale Price

$1,999.95

In Stock (10+)

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Usually delivered within 2 days

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Product Details

The Holley EFI Terminator X Max 550-916 is a complete standalone engine management system designed specifically for GM LS1/LS6 engines with 24x crank reluctor and 1x cam sensor. This comprehensive kit provides full engine control and 4L60E/4L80E automatic transmission control, eliminating the need for modified factory ECUs or complicated aftermarket tuning solutions.

Advanced Features:

  • Real-time fuel map learning automatically adjusts fuel tables, eliminating guesswork in base tuning
  • 3.5-inch touchscreen LCD handheld with calibration wizard, tuning functions, and gauge displays
  • Free Holley EFI software suite for advanced laptop tuning and data logging
  • Genuine Bosch LSU 4.9 wideband oxygen sensor for precise AFR monitoring and control
  • Integrated 1-bar MAP sensor ideal for naturally aspirated or nitrous applications
  • High-impedance injector drivers compatible with EV1 injectors and most stock LS injectors
  • 4 programmable inputs (12v, ground, 5v, frequency) for sensors, trans brake, or nitrous activation
  • 4 programmable outputs (ground, PWM) for electric fans, boost control, nitrous control, or IAC systems

Advanced Control Capabilities:

  • Boost control with parameters for time, gear, RPM, speed, and safety limits
  • Single-channel nitrous control (wet or dry, progressive or non-progressive) with rich/lean safeties
  • Advanced custom tables for flex fuel, fuel pressure safety, and more
  • On-board diagnostic LEDs for ECU power, engine run, wideband status, TPS calibration, and crank/cam signals
  • Plug-and-play compatible with Holley EFI accessories including gauges, shift lights, modules, and digital dashes

Complete Kit Includes: 24x LS engine main harness, EV1 injector harness, 4L60E/4L80E transmission control harness, Terminator X Max ECU, ECU main power harness, Bosch LSU 4.9 wideband oxygen sensor, I/O harness, MAP sensor vacuum hose adapters (1/8", 1/4", and 3/16"), and 3.5-inch touchscreen handheld controller.

Pre-loaded with base calibration maps for common LS engine combinations, the Terminator X Max gets you from the garage to the road or track quickly. Whether you're building a budget-friendly street car or a high-performance boosted race machine, this system delivers professional-grade engine management at an accessible price point.

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

Color

Black

Crank Reluctor

24x

Datalogging Support

Yes

Distributor Included

No

Drive-By-Wire

No

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

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, Transmission

Throttle Position Sensor Included

No

Transmission

4L60E/4L80E

User-Tuneable

Yes

Warning

California Proposition 65

Wet Nitrous Control

Yes

Had the wheel I needed. Excited to get it in and first purchase with this company.

Ok

Good product

Price is affordable

Easy transaction

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