So I finally got around to checking out these manifolds I have in my parents garage (being in an apartment really makes working on the cars difficult until I can get over to my parents house) and trying to work on a game plan for porting these manifolds.
Porting: I think the general consensus when porting is that it matters more to increase the efficiency of the flow, as opposed to strictly trying to increase the volume by hogging it out. This basically means i'll be trying to address the flow through all the transitions between the upper, lower, and cylinder head.
Upper: The upper seems to actually have a pretty good shape, and flow ... really doesn't look like theres much work to be done here. The only things I can see to address would basically just be smoothing out the casting lines, there's not really much material that can be removed before hitting the gaskets on the side so ... I guess that's that.
Lower: The lower is where I think the majority of the work is going to be done. The inlets are more of a square shape, but as you can see, it has a very rough transition into the oval shape of the cylinder head with a rapid expansion. In my very limited understanding of fluid dynamics this is bad. Basically a large and sudden increase in volume will lead to a decrease in velocity, a big problem for trying to make power. Basically, i'm going to attempt to smooth that transition and avoid any sudden expansions or harsh edges to maintain both flow and velocity.
Its my understanding that the weight and flow of the air favors the side of the runner opposite the injector bung, so its shape isn't as important. That being said, there is obviously a ton of material that can be shaped and/or removed there, so i'm going to look to address that spot as well.
Really that's all I can think of: Smooth casting in the upper, Smooth transition in the lower, Reshape injector bung. Also, this manifold is disgusting... I cant stress the importance of an OCC enough. At any rate though, any questions, comments, or concerns before I get started in the next few days are more than welcome. Thanks.