computer controlled turbo technology

[isham-research.freeserve.co.uk at pop.pol.net.uk]

> Not unless it annoys you- the turbo whistle is usually getting out through
> the intake, and the louder the whistle, the more open the intake is.  Some
> cars have sound filters to hold the noise in because it's irritating, but
> I rather like it. (-:

One of the changes between the WR ur-quattro and the MB was the
introduction of a silencer in the intercooler intake.  It isn't
illustrated on ETKA, but the same change was made to the Type 44 -
see A20Q/88/1/45/21-60 items 2 & 3.

This suggests to me that Audi found the intercooler itself to be
the radiator of the whine.  Their change certainly works - there's
almost zero turbo whine from the MB or RR ur-quattros.

--
 Phil Payne
 http://www.isham-research.freeserve.co.uk/quattro
 Phone +44 7785 302803   Fax: +44 7785 309674