Cold air box as it is now. Fabricated from 2.0mm ally sheet covered with insulation. Unfortunately this will not fit with H6 setup so will modify this one and make another for the other side
The picture shows the bathtub like nature of the intrusion (from the guide to the port divider) this is ca5mm deep.
The valve bowl/throat is small (for the valve size), and flat sided, I increased the throat cross sectional area to match the inner dia of the valve seat, there is not much material to play with, so be careful
. There was just enough material to allow removal of the port intrusion. On the worst dog leg port, the part which limits the csa is just beyond the area where the two valve ports join.
The port on the right is the original port, with minor cleaning up to help mould release. The dirty nature (and poor curing) of the silicon on the left hand mould makes the port look a lot more uneven than it was. I used silicon moulds so I could keep a check on cross sectional area, most get cut into 1cm sections which is why the mould on the left is full of inclusions (made up too much silicon and it started to go off before I had finished).
I don’t have any moulds of the finished ports, I will take some pictures