Cracked two-part manifold

[QSHIPQ at aol.com]

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Motor mount failure can exascerbate cracking problems, even on better
designed manifolds.  WRT "no amount of support to the wastegate" making the
slightest difference, is only opinion, not supported (pun intended) by theory
or documentation or audis own retro engineering.  My own question still
remains Phil:  The urS4 uses the exact same motor mount, and it fails
regularly without manifold cracking.  With proper support of the EM/turbo,
proper single pc manifold design and WG location, the *motor mount* failure
is not the cause of manifold cracking.

I expect that all 5k/200/urq's without manifold/turbo support will cause
manifolds (single or 2pc) to crack, some faster than others (as you noted)

Why don't the 20vt motor mount failures cause cracking?  No the 2pc manifold
is NOT the only solution (it is a darn good one, but manifolds and turbos
need support and good design), as audi went back to the single pc manifold
design on the later S cars without the associated cracking problems.  What
changed?

SJ

Phl Payne delectates:
>Note the location of the crack - underneath the manifold and on the other
side of >the bellows join from the wastegate.  This wascaused by a collapsed
right engine >mount, and no amount of support to the wastegate would have
made the slightest >difference.  Italso illustrates that the two-part
manifold - while it MIGHT be part of the >solution, is certainly not all of
it.  This manifold wasfitted by a UK specialist whose >name is almost
certainly known to you and lasted just 4,500 miles.  It was replaced >with
asingle-part that's still going strong after 12,000 miles - over a new engine
>mount and heatshield.I apologise for the poor quality, but at least it loads
quickly.