Exh flow numbers for the FE power Cyl heads, with the SE exh port and 1.675" valve.
Hopefully, the Tunnel Port heads with the SE exh ports (Pictured), will have the flow numbers as good as the FE power heads or at least close. I, am mentioning this because, From what Jay said, their not exactly the same, and so the flow numbers may not be either, and until we have the ports flowed, the numbers are a guess.
The chamber in my SE and RE heads is better for flow than the tunnel port chamber I designed. The reason is that the valves are moved towards the intake side of the head, making them closer to the center of the bore with my SE and RE heads. This allows for a more gradual turn to the deck on those heads than is possible with the tunnel port design, or any FE design for that matter with the stock valve location.
The bottom head is a TP with the stock exh, to compare with a TP with the SE exh.
TP With SE Exh Port
TP With Stand Exh Port