Until you talk to some one who is a head porter and tells you he did a set of heads that only flow 215 cfm with tiny ports for a 450 ci Buick that runs 10.9s @ 3500 pounds. According to the Moroso slide rule that's 480hp with 215cfm of flow. 2.23 hp per cfm.
In my view trying to calculate intake port velocity is a waste of time as a flow bench is not a running engine. Maybe a better way to view the problem is how does too much port velocity manifest itself as a problem in a running engine?