I recommend getting David Vizard's book Porting and Flow Testing. He describes his "really cheap flow bench". Does not read out CFM but does indicate where air is flowing if you get flow balls and pitot tubes.
Understanding where the air wants to flow and where flow is dead is important. Developing or improving swirl in the combustion chamber is highly beneficial.
In the ports, increasing cross sectional area may not provide the benefit you are looking for. The same goes for a mirror smooth surface in the port. 80 grit stones leave a beneficial rough surface that aids mixture suspension.
