#309-606 ThunderMax® With Wide Band Autotune for 2025 Center Cooled Softail Models®

ThunderMax® is complete system designed specifically for EFI equipped Harley Davidson® motorcycles.

This highly advanced, stand-alone tuning system utilizes proprietary AutoTune technology specifically designed to interface with wide-band oxygen sensors to correct abnormal A/F readings over a wide range of throttle positions and RPM ranges to prevent over rich or lean conditions.

ThunderMax® is made in the USA and comes assembled, no wire-cutting or splicing required to install. Replaces factory ECM and narrow band oxygen sensors.

*Supports RDRS function on 2025- Up FX Models.

Not legal for sale or use in California on any pollution controlled motor vehicle.
Not legal for sale or use on any EPA pollution controlled motor vehicle.