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ThunderMax for M8 Softail® Models
$1,088.95
ThunderMax is a performance-driven, award-winning ECM built exclusively for EFI-equipped Harley-Davidson motorcycles. Designed as a stand-alone replacement for the factory ECM, arrives fully assembled with wide-band oxygen sensors, plug-in harness, AutoTune module, USB communication cable, and everything you need for a straightforward install, no wire-cutting, splicing, or dyno required.
At its core, ThunderMax uses proprietary AutoTune technology and a closed-loop control system to continuously read, adjust, and perfect your air/fuel ratio in real time. With fueling points mapped every 1.5 of throttle and every 256 RPM, the system delivers unmatched precision for smooth, consistent performance in all riding conditions. A built-in barometric sensor accounts for altitude and ambient air changes automatically-just load the map that matches your build and ride.
The ThunderMax also features knock correction for timing adjustment, adding another layer of performance by adapting ignition timing on the fly. Unlike other aftermarket tuners, ThunderMax fully supports factory features, so your ride modes, Wi-Fi, and navigation all continue to work seamlessly.
Riders get complete flexibility run a base map and let AutoTune handle the rest, or dive into the ThunderMax software to fine-tune AFR maps, ignition timing, startup fuel, idle speed, rev limits, and speedometer calibration. The system also offers robust data collection and diagnostic capabilities, letting you log, monitor, and analyze critical engine metrics for deeper insight into performance.
The result? Sharper throttle response, stronger rideability, and that deep, tuned exhaust note that makes the bike yours. Compatible with high-performance cams, turbo, nitrous, and supercharger applications, ThunderMax 309-606 is engineered, built, and supported in the USA.
Notice ThunderMax ECMs utilize 18mm O sensors. Factory exhaust systems are equipped with 12mm ports; however, nearly all aftermarket exhaust systems are manufactured with 18mm ports. If using a factory exhaust, you may weld in 18mm bungs. Bungs are not included.
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 produ