Description
🏁 M8FI Gen 8 Harley Fuel Injection Controller Touring (G7 Non-Integrated or G8 Integrated)
For 2017–2020 Harley-Davidson® M8 Models
⚠️ RACE USE ONLY: Not legal for sale or use in California or on any pollution-controlled vehicles.
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
- 2 Bar Turbo (210 kPa / 15 psi) – Includes 2 Bar MAP Sensor and Jumper Harness
- 2.5 Bar Turbo (265 kPa / 22 psi) – Includes 2.5 Bar MAP Sensor and Jumper Harness
📦 What’s Included
- Your choice of 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

🎥 M8FI G7 Non-Integrated (2017–2020) Installation Video
📸 M8FI G7 Installation Photo

🧹 M8FI G7 Non-Integrated ECU – 2017–2020 Installed Under Seat

🔧 Bosch LSU 4.2 Wide-Band O2 Sensor – Front Cylinder

🔧 Bosch LSU 4.2 Wide-Band O2 Sensor – Rear Cylinder
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