Bernoulli and 350 ft/s, 146 cfm/in²

As with many calculations of this type, the most simple forms of the equations make a lot of assumptions and eliminate some of the more complex variables. The most simple forms of Bernoulli assume incompressible flow that is also non turbulent and frictionless. Non of those assumptions are true in the running engine. This means that it is quite difficult to write an equation that would accurately define what is happening at any given time in a running intake port.

What we can do however, is use Bernoulli to define something that is perfect, some ideal condition that we can never achieve. That sets the bar or the goal of 100% efficiency. Then we can measure against that standard and see how well we are doing.

For me, this whole line of thinking started as I was flow testing the heads and trying to understand why flow stops. Why does 28 in of differential pressure only push air so fast?

I understand the arguments against Bernoulli. But I also understand this - Bernoulli can be used to predict a theoretical limit of 146 cfm/ sq in of flow area. The very best hemi heads don’t quite get there, but they are extremely close.

Let me also say that I appreciate the questions and the feedback. I am searching for answers and understanding. All of this interaction really helps.