Well educate a mug. What's so important about volume? Isn't port flow much more important? Or more accurately asked...."what" you need to be paying attention to?
Port size affects air speed. You have to manage the speed of the air. If the port is too small you can’t control the air speed especially around the short turn.
Plus, you have to have enough port size to feed the valve/bowl. 9 times out of 10 when you see a head break over and lose flow on the bench it’s because port can’t feed the bowl and valve size, the air speed goes through the roof and whamo, you get the break over.
