TweakyourAPC ! 

Bypass R42 - Replace R138 with 40Kohm
Replace R40 with 1,3Kohm OR Replace F-pot with 1Kohm linear pot OR Install 300 ohm resistor in parallel with pressure transducer.
Adjust F & P to taste, P for boost rise rate, F for high RPM boost pressure
Townsend APC info, Baseboost etc
The original source of Saab 185hp RedBox mod.
Thanks to Kevin K, Kalle K, Anders Olsson, Widde and many others Keep on SaabinŽ
APC tweaking since 2000!!!
Click for a screenshot from 5.10.2000
Updated 18.4.2008 / MA