Hi Everyone,

I have been working on an intake for my 95 miata. The part routes through a very narrow space near the front of the hood and then through a factory hole in the bumper support. I started the project with an expanding foam pour, 3d scanning, and about a dozen design variations using 3d printed ABS plastic.  Abs has help up well so far but I want to start making versions out of carbon fiber. My current plan is to print two molds for interlocking silicone plugs that have a removable plastic core. I would then do my layup over top, remove the plastic core pieces creating an air space in the center of the silicone plugs. The air space would allow my to deform the silicone enough to remove it from each end.  Is this a reasonable plan? Alternatively, is there an inexpensive soluble casting material I can use that doesn't shrink very much?

Also, I am also planning to redo the aluminum crossover pipe in carbon with an integrated heat shield to reduce sensor heat soak. Is there any issue with doing a wet layup on top of a cured part if I provide a reasonable amount of surface contact area? Would I be better off curing both parts and using a structural epoxy?