Description

 M8FI Gen 8 Harley Fuel Injection Controller Touring (G7 Non-Integrated or G8 Integrated)
For 2017–2020 Harley-Davidson^® M8 Models

The M8FI Gen 8 Harley Fuel Injection Controller Touring is a professional-grade plug-and-play ECU engineered for closed-course competition in the King of the Baggers series. It offers a complete EFI and ignition control solution for highly modified V-Twin engines.

Notably, the M8FI ECU solves tuning challenges caused by long-duration cams and unstable MAP signals using advanced Alpha-N strategy.

 Key Features of the M8FI Gen 8 Harley Fuel Injection Controller Touring

•  Fully reprogrammable replacement ECU
•  Alpha-N fuel control (RPM + TPS) – unaffected by long duration/high overlap cams
•  Auto-Tune included – wide-band Bosch LSU 4.2 sensors for both cylinders
•  G7 = Non Integrated Modular Design – wide-band controller and USB interface are separate units
•  G8 = Integrated Design – wide-band controller and USB-C interface built into the ECU
•  G7 and G8 ECU’s function the exact same on the motorcycle
•  Continuous data logging – 60 minutes at 10 samples per second
•  Windows tuning & logging software (XP through 11)
•  3D tables for fuel & ignition; 2D for idle and enrichment
•  User-configurable I/O – nitrous control, RPM limit, Ignition kill (in between gear for air shifts), and more
•  Integrated Support for Cruise Control
•  Billet aluminum housing with black anodized finish
•  Plug-and-play harness and installation
•  RDRS Compatible 

 ECU Configuration Options

• 1 Bar Naturally Aspirated (105 kPa) – Utilizes the OEM MAP Sensor

 What’s Included

 either a G7 or G8 M8FI ECU

• Bosch LSU 4.2 wide-band O2 sensors (front & rear)
• USB-C programming cable
• Installation & tuning guides (PDF + video)
• Access to PC_LINK & TCFI_LOG software

 Software & System Requirements

• PC_LINK v23.6+ for tuning
• TCFI_LOG v19.99+ for logging and diagnostics
• Compatible with Windows XP, 7, 8, 10, 11
• Free download & demo mode available

 Documentation & Downloads

• G7 Non-Integrated ECU Startup / Setup Guide (PDF)
• G8 Integrated ECU Startup / Setup Guide (PDF)
• PC LINK Tuning Guide G7-G8-G9 (PDF)
• Software & Driver Downloads

 Maximize Power with the M8FI Gen 8 Harley Fuel Injection Controller

The M8FI has been tested on engines up to 145 CID and over 250 RWHP. It comes preloaded with a base tune file for fast startup. Additionally, the integrated Auto-Tune adapts to changes on the fly. This significantly reduces dyno time by enabling real-world tuning under live conditions.

 Advanced Tuning via PC LINK Software

Access 3D fuel and ignition maps, 2D idle and enrichment tables, and adjust all engine parameters using the included USB-C interface. The PC LINK software provides full control of your tuning strategy, all from a Windows-based environment. All M8FI software is free to download and includes demo mode for offline training and tuning.

3D Ignition Advance Table

3D Air/Fuel Ratio Table

Engine Control Parameters

 User Inputs & Outputs

Program user inputs and outputs for nitrous activation, ignition kill (in between gear, for air shifters), RPM limiting, shift light, or auxiliary control. These functions add flexibility for racers needing real-time responsiveness and safety triggers.

User I/O Configuration

 Data Logging and Diagnostics

The M8FI Harley Fuel Injection Controller logs up to 60 minutes of sensor data at 10Hz. You can view real-time dashboards or chart-based playback of AFR, RPM, TPS, MAP, ignition advance, and more. Furthermore, it provides operating stats, max RPM tracking, and histogram analysis for fine-tuning and diagnostics.

Real-Time Engine Data

Data Logging Chart Recorder

Diagnostic & Operating Statistics