2-piece EM: even more questions...

[Gerard <gerard@poboxes.com>]

Hi!

Me again going on about 2-piece EM for the
MC motor.

I am definitely forced to get one of these
things for the 200 and that means agent's
only prices. What has to be done has to be
done, I guess.

I'm still curious as to why this whole thing
fails the way it does. Hence the following
silly questions:

	1) what metal or alloy would one
	   use for the 2-piece EM to give
	   it better heat resistant properties
	   and make it stand up to heat for
	   longer, make it resist excessive
	   warping and make it tough enough
	   to resist cracking?

Maybe the same material the head uses? I think,
from what I've heard about the Dialynx headers,
is that casting the unit in the same material
but making it thicker, did not help the longevity
of the unit. It resists cracking, but apparently
it warps like crazy and is a b*tch to work with
(right Phil?). So maybe use something that does
sit with the heat very long or that takes a lot
of heat energy to heat up.

	2) what in the design of the 2-piece
	   do more knowledgeable listers think
	   the engineers should have changed
	   to make it a stronger unit?

	3) this one is for the turbo gurus on
	   the list: what would you change on
	   the design of the 2-piece EM to make
	   it work better in this turbo
	   application? I've seen some cars running
	   tube headers for turbos (none Audi
	   so far), so how does a cast unit
	   compare to a mandrel bent tube
	   header for the same turbo app?

If I get the 2-piece I am coating it, but there
is indication to leave it as is to do its job of
heat sinking. However, to me it seems the thing
hangs onto the heat too long and that is a major
factor in the cracking and warping of the unit.
Maybe the unit should have been cast in a material
more suitable to getting rid of any absorbed
heat.

Sorry for the WOB. It's sunday and I've feeling
silly again.

G.