[DMXF]

Gary - Yes, there are a number of factors that influence the overlap of the suction pulses in the plenum, although I'm skeptical whether the net average of all the cylinders changes that much. I believe the overlap will also vary with engine speed, indicated in one example by the piston stroke being out of phase with the cam profile which probably indicates air charge momentum continues to fill the cylinder after the piston is slowing down (and that effect would vary with engine rpm).

BTW, I had an email communication promting me to clarify that I used the wrong wording in describing the phenomenon of the weber curve fattening out. From the simplistic standpoint discussed here, the flow demand doesn't fatten relative to crankshaft position, but as you increase rpm the air velocity at each point along the flow curve increases because you're trying to pull the same amount of air (for our purposes) into the cylinder, but at a faster rate because the valve is open a progressively shorter time and the piston is moving faster (faster suction). So, after the peak flow point hits the limit, if you keep increasing rpm the flow velocity can still increase in the areas to each side of the peak.

I was thinking a little more about this max choke air velocity aspect and ran a few calculations. It looks like the airflow velocity through the 52mm choke is nowhere near the speed of sound I was advised could be a factor, so it would take a drastically smaller choke to get there. Therefore, I guess I'm at a loss as to exactly what phenomenon is driving the "ceiling" engine speed of the webers. What I did find is that the cylinder head port flow capability seems to be a big bottleneck, such that even a 350cfm intake port will start clipping the flow demand of the cylinder at around 5,000rpm. This sounds like the big reason why the torque peaks around that point on alot of these traditional V8's and drops off as you go higher (volumetric efficiency goes down).