All for .370 lift and under ........

273 said

I never got that the valve and throat is the most restrictive part then the bowl but also shortest part of the intake tract, wouldn't the mouth of the port and intake runner be the major contributor to velocity? Wouldn't make sense to make the valve and bowl to be able to keep up with the rest of the intake tract.

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The port cross sectional areas are fixed while the valve curtain area is constantly changing as the valve opens and closes.
SBF heads have challenging shaping with a fairly large intrusion into the port for the pushrods. But that area is still large compared to the valve curtain area, especially at low lift. DV teaches if you have a flow bench, look for the low hanging fruit first. That is the curtain area. When you get that flowing well you look to other areas in the bowl and then in the port.
In his book he describes his DV really cheap flow bench. It does not read in CFM but will show improvements. With pitot tubes, flow balls and thread strands in a tube you can see where the flow wants to go and turbulent areas. A pitot moved in the port senses pressure drop. A flow ball moved in the port will cause a flow reduction when moved to a high flow area but have minimal effect where the air is not going. The threads glued into a tube will flap around in the wind like a flag. If flow gets turbulent their motion will be caotic.