Not quite sure exactly how the overboost function works but I am fairly sure that there is not a button on the car itself to engage/turn it off.
From what the brochures tell me (
) the overboost kicks in automatically 'when you need it most'. I assume the electronics recognise if you are trying to do an overtaking type manoeuvre and then give more oomf from the engine accordingly.
Hope this helps!! Enjoy the Dooper!!
