I need to have 2 threaded fittings in this pipe, one for the breather return and one for the turbo pressure recirculation valve. These need to be M20x1.5. My original plan had been to bond in an 80mm section of 50x10mm aluminum flat bar, which I was going to bend into shape to fit nicely inside the pipe. Unfortunately this is proving to be much harder than I realised, and I can't bend the flat bar at all. In fact I can't even have it professionally bent, as this size flat exceeds the capacity of the local metal shops roller. 

For anyone interested, the stack was composed of 2 layers of 199gsm 2x2 twill carbon, then strips of the same fabric placed at 45* either end for strategic reinforcement. Then an additional 2 strips of uni close to each end where the hose clamps will be placed, followed by a final layer of the 199gsm carbon over the top.

Has some residue from the Frekote on it taking the sheen off, so will need to polish it up. Also had an issue with bridging on the straight end:

Luckily that's not too critical, I can just make that end a couple mm shorter if need be. Thought I had paid close enough attention to pushing the material into those corners, but obviously not. Will be more careful next time.

It's taken some time, that's for sure. Flatting that plug down only to recoat it and do it all again was rather tiresome. But definitely worth it in the end. There was no damage to my plug in the process either, so I can make another set of moulds if I need to.

Chris