AVS 2 CFM???

Plastic spacers are cheap (and depending on engine combo, can be the cheapest horsepower there is.... or not) and insulate better than aluminum.
They sometimes aren't available in exactly what you need.
I think I could fab something from plastic. What are we using? I have a lot of Corian. I plan on taking it to a local tuner guy with a chassis dyno. I would like to be armed with some options.