There's been progress on this topic; I just have not been able to get back to it in a very timely manner. As a teaser: Here is a quick and dirty of a prototype intake manifold under CFD testing. I have forgone the use of a diffuser for this run; just to ensure that if I can get a uniform flow at the entrance of the manifold I get a good flow at the runners:
Here's the initial design:
notice the poor flow distribution to the runners. This required me to alter the geometry of the plenum.
Here's the final prototype:
