ARMYTRIX have created a valvetronic, performance exhaust system for the BMW M3 and M4 (F80/F82) that makes one insane noise! Check out ARMYTRIX now: http://www.armytrix.com/BMW-M4.php
The Armytrix exhaust upgrade for the BMW F82 M4 enhances the performance and also the sound. In addition the Armytrix App works alongside an OBDII Module to allow valve control from Android or iOS devices.
For more information on ARMYTRIX, please visit:
Thanks for watching, Tim