I'm working on an engine and need to make some new intake runners,  i could make some tooling and have them cast, or machine them from solid, however, i'd like to have a go and see if i can do them from carbon. 

i've worked with fibreglass before, and used carbon in bought in sheet form, but never tried laying up my own carbon things.

my idea is to machine a block which bolts to the cylinder head, machine a block which bolts to the throttle body and clamp them into a split mold tool.   then block one end and fill the mold with investment casting wax.

once the mold is split, i can lay the carbon around the machined end parts and the cast wax.    once the carbon is finished i can warm the part to remove the wax, hopefully leaving a carbon tube, joining the two parts and with a decent surface finish on the inside.

i was thinking of using expandable carbon sleaving, with carbon tape at each end to neaten things up a bit. 

hopefully theres some pictures below to explain things a bit.


is this a reasonable idea or am i barking up the wrong tree?


the mold tool (mating half hidden) with two end pieces fitted




the mold tool with two end pieces and filled with wax (pink)




the part, ready to apply carbon