The D2 S8 has a donut-joint between the passenger side downpipe and cat, to allow the cat to be removed for access to the gearbox. Unfortunately most of them are looking pretty crusty by now, this one particularly so!
This is beyond salvation, and obviously unobtanium now - Prestige don't have any, and I don't have any good ones so time for a new solution.
Start with a 3D printed prototype to test fitment
That fitted the pipe quite well, so I sent the file to the local steel stockholder who CNC plasma cut me some flanges (minus small holes as the plasma won't cut them)
Drill mounting holes
Then stick it in the lathe and turn a chamfer in to one face to match the pipe
and then cut the lovely thing in half
Alas, this is the only way to get it on to the pipe.
Using the other flange, I bolted it all together to get it straight while back on the pipe. The pipe is covered in anti-spatter spray and I also used some aluminium foil between the new flange and the pipe so I didn't weld them both together.
Then attacked it with the mig, and we have this
I think this should work just fine, and I went slightly overkill and made it from 10mm plate, so it should last a few more years
I need to do the same again to the cat which has the other side of this tomorrow, and then hopefully it will all bolt back together nicely
