Originally Posted by 328i M-Sport
Higher octane is more resistant to detonation. It can make more power by not reducing timing to avoid knocking.
If the car does not have a high compression engine or advanced timing, it will not benefit from it. Higher octane gas in theory actually burns slower. And most brand name gas stations put the same cleaners into the fuel for any octane.
Burns slower? Say what?
It will burn inside the burn parameters in a tighter range but not slower. Just more controlled.