That i cant answer but i still think it does not have any effect. This is advanced physics + fluid dynamic + calculus.Ermmm sound reasonable too, What in you mind think if the flank its shorten ? from my oppinion turbulance that create its more for giving forced air into the combustion system. "create wave wind intake stroke"
Just to share, an automotive student did a test/study on the spiral intake thing which claimed to provide better power and better fc. Test is done with a dyno. I know the device is commonly fitted before the TB but I dont recall if the device is fitted before the TB or after the TB for the test.
No gain at all but reduced a few hp and Nm on the dyno.
I think the vacuum generated by the piston going down in the cylinder does not like any sort of restriction in air flow, just like our vacuum cleaner at home.