G63 AMG [W463A][2018-]

These video clips should help give an idea of expected sound improvement (although not the exact model)

Reworked backpressure valve control unit, which is freely programmable. This control unit provides the possibility to individually program the pack pressure you would like to drive in. This way, you can reach the maximum engine performance. The portion of back pressure resulting in a loss in performance is filtered out. Therefore, this controller combines all advantages in both, the lower and higher range of revolutions (rpm), since the back pressure can be exactly dosed to enable the engine to gain the maximum performance.
This new unit has control-LEDs and a RDS transmitter, which sends the values and functions to the car radio's display. It can be adjusted by the remote controller (key fob). 

a) in Cruise mode - the exhaust gas valves open later
b) in Sports mode - the exhaust gas valves open earlier

In both, the cruise mode and sport mode, you can individually program when the exhaust valves shall open. One big advantage is that the control unit recognizes the driver’s operation characteristics. If the driver accelerates aggressively, this is identified by our device by the kind of back pressure that is generated, and the exhaust valves open immediately. Usual acceleration results in a later opening of the exhaust gas valves.

ADVICE: Connect the controller to ignition current (not directly to the battery)!