Hmm, can't see that in the pic .. Looks like it just goes straight into the steel wall and somehow merges into the main pipe ..

Seems very very restrictive as soon as it comes out the back of the Turbo? I'll have a look at my old standard dump when i get home and see how that works.

I figure that when the WG opens, you want that gas to free flow out, into a seperate pipe the join up short time afterwards.