exactly sir, so the higher the cylinder filling the faster (and greater volume) the gasses will be exhausted lol so to increase cylinder filling (more gas) you could for example change the cam (so volumetric efficiency is greater at a lower rpm) and port the inlet (clearly you would do the inlet and exhaust). There is more gas in the cylinder to be pushed out in the SAME amount of time, tbh i think volume is much more important than velocity up until a point in turbo spool up. Looking today, i think the ports are big enough to flow enough lol they are pretty massive! even as standard. I agree with crazy cage that improvements can be made however they will not be vast, at least not as vast, or important as the inlet.