Early in their development the Porsche 908 had a dual plane crankshaft and a flat 8 engine. In essence they were operating as two flat 4 engines 90 degrees apart in firing sequence. That is, the engine had one firing pulse each 90 degrees of revolution. This configuration had such a high vibration level that it actually broke the frame of the cars and destroyed electrical components. They then shifted to a flat plane crank with each rod having it own journal turned 180 degrees from its neighbor. Doesn’t this mean that the engine had two simultaneous firing pulses each 180 degrees of revolution?