Boost levels

[Smeins, Larry]

The spring works against ambient pressure and allows boost to go .2 to .3
bar above ambient.  Ambient in Denver is 0.8 bar so spring limited boost is
from 1.0 to 1.1.  I've observed a maximum WGFV duty cycle of 50% on my 5kt
which produces 1.2 bar.  If I disable the WG I can readily hit fuel pump
cutoff.  It appears the factory has built in limited boost at altitude.  A
heavier spring should bring the boost up.

If working correctly the boost indicator should read 0.8 with the engine not
running and ignition ON, in Denver.

Larry
in Loveland

Message: 7
Date: Sat, 28 Apr 2001 18:59:56 -0600
From: Jon VonOhlsen <jvosvan at rmi.net>
To: quattro at audifans.com
Subject: Boost levels

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> Does anyone know the normal stock bar boost range of a 1989 200?
> mine is .4 bar before starting,
> I remember reading it somewhere being up to 1.2 bar,  I just cant =
> confirm it. I usually am getting up to 1.0 bar boost.
> btw 'am 1 mile above sea level in Denver
>
> Oliver M. Llenado
> Homepage http://www8.ewebcity.com/omllenado
>
> -

Oliver,
Check out http://www.sjmautotechnik.com/
as the boost mapping is decribed there. I am also in Denver and I also see
about
1.2 bar when floored in 3rd. At lower elevations it is 1.3 bar. I suspect
strongly that our cars boost is being controlled by the spring ONLY. This
should
result in a fault code, but I do not get any fault codes.  Typically, one
should
see around 1.4 bar stock, and it should come on around 3K.
JonVO