According to this video, when two flame fronts within a cylinder, one resulting from the spark of the spark plug, and the other resulting from the following increase of heat and pressure from the original flame front, meet, high-frequency pressure waves are produced, and cylinder pressure increases dramatically. So, what exactly is going on? Is the gas in the cylinder combusting more rapidly, and therefore delivering the same amount of power in a shorter period of time, resulting in the cylinder having to experience higher pressure than usual? What exactly happens when the two flame fronts meet? One is exerting pressure in one direction, and the other is exerting pressure in the opposite direction.