2021 - 2024 Harley Davidson Softail Tuner by ThunderMax ECM. 

What is ThunderMax ECM?

ThunderMax is an award-winning performance ECM (Engine Control Module) designed specifically for EFI-equipped Harley Davidson® motorcycles. This cutting-edge, stand-alone tuning system utilizes AutoTune technologyalong with wide-band oxygen sensors to provide unmatched performance and rideability.

Whether you're looking to improve throttle response, engine smoothness, or overall bike performance, ThunderMax offers a complete solution that enhances your riding experience. It is 100% assembled and ready to install, so you can enjoy enhanced performance without the hassle of complicated setups or wiring modifications.

Key Features of ThunderMax ECM:

• AutoTune Technology for automatic fuel adjustments
• Wide-band O2 sensors for precise air-fuel ratio control
• No wire cutting or splicing required for installation
• Fully assembled and ready to install
• Adjustable with ThunderMax tuning software or by loading a basemap

Effortless Installation for Instant Performance Boost

ThunderMax ECM comes completely assembled, meaning it’s ready for a simple, hassle-free installation. There is no need for complex wire cutting or splicing—just replace your factory ECM and oxygen sensors, load a map, and you're good to go! It’s an easy way to upgrade your Harley Davidson® without any technical headaches.

ThunderMax ECM Installation Process:

1. Remove your factory ECM and oxygen sensors.
2. Install the ThunderMax ECM and wide-band O2 sensors.
3. Load your chosen map to enhance your engine's performance.
4. Enjoy a smoother, more responsive ride with improved throttle control and overall engine efficiency.

Real-Time Auto-Tuning for Smooth Engine Performance

ThunderMax uses AutoTune technology to automatically adjust fueling every 256 RPM and at every degree and a half of throttle. This dynamic system ensures that your engine runs smoother and performs better across a wide range of conditions.

With the built-in barometric sensor, ThunderMax automatically compensates for changes in ambient air pressure, meaning you don't have to manually adjust settings for changes in weather or altitude. The wide-band O2 sensorscontinuously monitor the air-fuel ratio and provide real-time feedback to the ECM, ensuring that the engine is always operating at optimal performance levels.

Benefits of ThunderMax ECM's Auto-Tuning:

• Automatic fueling adjustments at every 256 RPM for smoother performance
• Real-time air-fuel ratio feedback via wide-band O2 sensors
• Barometric sensor automatically compensates for weather changes
• No need to manually approve changes—once you turn the bike off, all adjustments are saved

ThunderMax ECM: Fully Adjustable for Custom Tuning

The ThunderMax ECM is designed to offer maximum flexibility in tuning your Harley Davidson®. You can use ThunderMax tuning software to make detailed adjustments to the ECM, ensuring it fits your exact riding style and preferences. If you prefer a more straightforward approach, simply load a basemap and let the ECM automatically optimize the engine's performance.

ThunderMax Customization Options:

• Fully adjustable via ThunderMax tuning software
• Pre-loaded basemaps for a quick and easy setup
• Comprehensive tuning options for riders who want full control

ThunderMax ECM: The Perfect Upgrade for EFI Harley Davidson® Motorcycles

Whether you're looking for smoother throttle response, better fuel efficiency, or improved overall engine performance, the ThunderMax ECM is the perfect solution for EFI-equipped Harley Davidson® motorcycles. Designed to meet the demands of performance enthusiasts, ThunderMax delivers a ride that is more responsive, smoother, and more powerful.

Why Choose ThunderMax ECM?

• Superior performance with automatic fuel adjustments for every throttle change
• Smoother engine operation with real-time air-fuel ratio tuning
• Easy installation with no wire-cutting or splicing required
• Customizable tuning options to suit your unique riding style

Upgrade your bike today with the ThunderMax ECM and enjoy a more powerful, responsive, and smoother riding experience. Whether you’re cruising on the open road or navigating city streets, ThunderMax ensures your Harley Davidson® performs at its peak.

Installation Instructions

Emissions Notice

This product is intended for "RACE READY" vehicles only and is not for sale or use on vehicles otherwise subject to emission control requirements.  In the state of California, this product should not be used on any vehicle that is registered for use on public roads. Please view the ThunderMax 50 application guide for "STREET APPROVED" & ARB compliant products.

Note: Models equipped with Traction Control please email Support prior to installation for proper firmware download.

Part Number: 309-592