I'm looking for some general advice on making an intake plenum to suit a low boost turbo engine (7 PSI) out of carbon fiber using vacuum infusion, utilising my 3D printer to create the mould. This would be the first carbon fibre part that I've made, based on a design drawn up in Autodesk Fusion 360 shown below.

So far I've spent a few days doing research online, reading other posts in this forum relating to intake manifolds and 3D printing moulds and watched numerous videos on producing carbon fibre parts. However I still have a few open points I'd like to get peoples opinion on. 

• Based on the plenum shape I'm assuming I would create a positive mould.
• Should I use tooling gel or something like 3M Super 77 sparingly to ensure the CF attaches to the shape.  
  
• Does this sound right to create a 3D printed mould; use PLA filament, smooth down the edges, spray a few coats of plastic filler primer and seal with S120 mould sealer.
• For the 4 bolt end flange I'm guessing this can't really be formed using CF. Instead could I go about inserting an aluminium flange that could form part of the mould and be covered in CF. Would this hold up under boost? 
• Layer up wall thickness to be around 2mm, from what I've read this would be strong enough.

I would like to kind of disagree with both of you.

-Except for interlaminar stress, carbon has excellent duration fatigue strength. And as the plenum should be under pressure from the turbo, I don't see any reason, why interlaminar stresses should be an big issue here. So I don't see any reason why pulsing forces should be a problem here.

-to say: carbon is stronger than steel, have you ever seen an aluminium or steel plenum collapse?, is in many ways a misleading point.
Carbon is in almost all cases not stronger than steel. The fibre itself under tension, yes. But most real life multidirectional laminates with 50-60% fibre content under complex loads are not. The higher the resin contend (to a certain degree) and the more the load differs from an simple unidirectional tension (so you have to include different fibre orientations) the better steel gets in comparison. In most cases, you could get strengths that exceed those of steel, but usually not with "lay up 4 layers of 240g". This needs knowlege and understanding of the exact forces and fibre orientation, as well as some calculations. Far more crucial here is the fact, that both steel and aluminium fail through deformation, while carbon is far more likely to break into pieces, which could enter the engine.
And the new plenum has a diffent shape, different wall thickness, etc.. that's like comparing apples and oranges.
Especially the "joint box profiles" with many plain surfaces and corners, shown earlier here, could be a real problem when applying internal pressure. And those are very likely bad from an aerodynamical standpoint as well.