[Henry Floored]

I have flowed baby powder through Flathead intake ports. On the exhaust port outlets I simply started a Flathead without the exhaust manifolds on to get an idea of what the exhaust flow was doing at the outlet area. In both cases the visual is very telling. It's very easy to see that at both of these visible points the charge "wants" to go straight. In the intake port it is shooting straight towards the center of the cyl head dome and on the exhaust port outlet it is blasting straight towards the center of the engine just like Bruce said that Flatdog found. The idea of a very center angled or even slash cut out ext header pipe is probably the best way to carry the charge out of all 4 outer ext ports. Precisely what Flatdog was doing.