SV: Adjusting Boost

[Michael McBroom]

DemonTSi at aol.com wrote:

> << There is always a problem when You whant some high power output from this
>  systems because the boost will rise very quickly in high gears and then
>  when You are at peakboost the knocks makes the ignition to retard (if the
>  ignitionsystem have a knocksensor) rapidly so then You have lost all power
>  again (boost goes down and ignition retards at the same time)
>  I remember that we made some modifications in the system and sold it as a
>  tuningkit for Saabs. I can not tell You every mods (still selling a few)
>  but the system works better if You shortcut resistor R42.
>  We are selling the kit with the P-pot installed on the dashboard together
>  with a chip for the enginemanagement. >>
> 
> If the system also retards the ignition timing...then does that mean that it
> is connected to the car's ECU? Can the Saab APC be used as a totally
> independent boost controller?

Stefan was referring to the Bosch ignition system, which retards the
timing when detonation is detected.  I don't know how he does the APC
installations on non-Saabs, but on my Volvo, I piggybacked the APC knock
sensor on top of the ignition knock sensor (they're both identical Bosch
units).  So, what happens is, when pinging is detected, both boost and
timing are retarded.  It makes for a safe combination, but if one wants
to go fast, one had better figure out how to stay out of detonation :)

-- 
Best,

Michael McBroom

'87 745T 123k w/APC                 Visit the Volvo Performance Site:
'88 765T 156k                           http://mcbrooms.com/volvo
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Graduate Student, Linguistics                         Author of 
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California State University, Fullerton			
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