Finally Weapon-R Secret Weapon intake installed.

[Grif]

You only want to reduce the oval shape to something the same circumference as the flexible tubing...something like the rectangular pick up from a vacuum that connects to the hose...same principle of changing from one shape to another but without losing any of the flow.

Correct, but that isn't a reduction, its simply changing the shape of the air pickup while maintaining the surface area of its cross-section. I do not know if that is possible using that oval hole, but I'll look into it. Thanks!