adjustable WG cap mod, & other incremental increases

[Gerard]

> So, the failure mode for single piece MC EM's is actual cracking?!
> I remember hearing about warpage, but I don't recall mention of
> cracking.  I'll have to look into that.

The single piece MC EM sitting in my garage right now is warped and
cracked quite badly. It had already been welded once before, and
ofcourse it cracked right on the weld again. This thing was incredibly
noisy on the car.

The main crack is all the way around, actually right where Audi seem to
have put the join on the 2-piece EMs. The 2-piece is also not the
be-all-and-end-all of preventing cracked manifolds. I sent my 1-piece in
for welding as it had a hairline crack on the front piece near the join
between the two halves and also had a crack on the vanes of the
collector on the turbo end. This seemed to extend all the way through
the metal.

The odd thing is that I have another 2-piece EM and the thing has the
same cracks in the very same locations. I suspect the other one arriving
in the next week or so will have the same cracks.

> Maybe the warpage I've always seen referred to was the Dialynx
> unit.

I recall someone saying these warp, but don't crack. Much heavier than
stock and apparently a real pain to install. The 2-piece is alot beefier
than the 1-piece and I think the Dialynx is even thicker. I've never
seen a Dialynx, just going on what I recall from list traffic.

I haven't even got a clue what iconel is. High nickel content cast iron?

G.
-- 
gerard at poboxes.com
q-list info: 1989/90 200 (mac13a MC-1)