I take it back, these copy joiners even have an o-ring groove for the stock o-rings I'd assume, but I'll get some newies!

Not quite sure what you mean mate, but the plumbing is firstly that preformed ( deformed! ) alloy tune and roughly 2" at that point, rises to 2.5" pre intercooler, and is 2.5" all the way post IC ( except the massive bottleneck at the EGR ). I'll copy that to the letter, but with real tubing and quality silicon " hump" joiners. The fittings themselves are very specific, and a large C clip basically holds them in place, there's two teeth 180 degrees apart, and a corresponding window through which the clip holds the teeth.

I'll try and take a pic, but the basic problem is you really need these specific spun adaptors, even APR do one in their top end intercooler kit. Porsche have similar fittings apparently, and I've only heard they leak over at TDI club, so no real life experience there for me as yet.

When I'm done, mine won't leak!!

I'm at the stage of being ready for a mock up inlet, just need a clear weekend and I'm into it.