custom 4 fiber tube

ok, heres what im needing advice on...  I want to make a custom 4" intake for my truck.  It needs to be a 4" ID tube with a 90 degree bend in it.    I am looking at getting some carbon fiber cloth to make it out of...  Only problem is is that i cannot figure out how to make it all one piece.   I cant get a 4" OD pipe that has the 90 degree bend in it to us as a mold because i wouldnt be able to get it out from inside the hardened cloth....  What else could i do to make this work??  Could i maybe just do the 90 degree section, pull the pipe out and then make the straight pieces attached to it..  it would be like a 3 stage process but if it would work that would be ok....  If anyone has any ideas, please let me know....  Thanks for the help

why not make the mold shape out of styrofoam. then after you have laid the fiber and it has hardened, just destroy the foam either by mechanical means or chemically. plenty of chemicals will dissolve styrofoam. hope that helps.

i could, but that would only get the tube shape on the outside...  What about the inside??  i need something that will give it an open round shape on the inside

I think he is saying use styrofoam and shape it so you can lay the carbon over it.  I would just buy a big block of styrofoam or go to a crafts store, and get a block of that roam that can be shaved, sanded, cut, etc. and make a 4" OD 'pipe' that you can wrap the CF around.  Just carve it the exact shape that you want to wrap the CF over.  To make sure that the inside of your intake is smooth, and does not come out bumpy like the surface of the foam, wrap the foam with masking tape, and use some mold release or PAM spray on the tape before laying CF on it.  Once the CF epoxy hardens, grab a spoon, and scoop the foam out of the intake.  If you want to get a nice shiny CF finish, you are gonna have to sand with several different grits, etc. clear coat, wet sand, etc.