318 head flow

skrews said
We've done that with the 1020 bench I use, and it gives lower numbers than the other 2 1020 benches tested. You'd be surprised at how much difference the clay radius can make. SF will also tell you that their 600 bench by design will give higher numbers than a 1020. The Sanez brand benches will give higher numbers than their SF counterparts.

Crazy stuff.
Makes the before and after very important to see what you're doing it for.
I use clay, its finger formed... and cheap.
If playing with runner/window size then you would have to develop a port ..say 3 ways/flow profiles, find that window dimension/s and then make radius plates for each to flow them.