Blue2000S,
Thanks so much for doing the leg work for the members of the Forum. I didn't realize there was so much to getting the real numbers. Like I said, I thought you could just put a flow meter on and read the delta. This is obviously the correct way to do it. If I understand your last statement, the difference is 5-6% or about 24 CFM increase over the 400 CFM @ 7200 rpm.
Power increase if any? My guess is the engine would enjoy the better breathing. Again, thanks to Blue2000S for the great work.
Beers on me if we ever meet.