Re: Compression decreasing block on MC turbo engines...

["Bruce Bell" <bbell@bbell.com>]

> From: DeWitt Harrison <de@aztek-eng.com>
> At 08:57 AM 11/14/97 +0200, "je'rard" wrote:

> >I suppose if I did hunt down S4 pistons (which seem to
be in abundance
> >at the Audi/Porsche stripping works in Johannesburg
(??!!??)) I would
> >need to gain more air flow by fitting the 20V head as
well, right?
> >Say, if I coughed up the dough and bought the S4
pistons, would they fit?
> 
> Dunno offhand.

Yes, S4 pistons would fit the block; they do need to be
matched to a 20V head. Think about the combustion chamber,
it is a different shape and volume. If you want pistons for
a 10V head there is a plethora of them out there. Look to
the VW parts bin. 
 
> >Isn't the S4 a 2.5 litre motor? I spoke to someone at
the stripping
> >works and he said the job would need new con-rods and
crank as well.
> >True? As for dual knock sensors, I have them already.
 
The S4 (U.S. AAN version) is a 2.226 litre just like the
MC, JT etc.
 
> It would be cheaper and far more effective to swap out
the whole bloodly
> thing at once. Wiring harness too.

Good advice!