Date: Mon, 01 Dec 1997 00:42:09 GMT From: Ywan Mason <ymasonnopsamsouth.net> Subject: Re: APC controll unit
Leave it alone. Saab engineered it as it is to save the engine. Its responsibility is to limit knock, not provide max boost. When you up its max allowable boost, you defeat its knock limiting ability and endanger your motor. The APC solenoid that is uses to regulate the wastegate on the turbo operates at 60Hz. If you allow too much boost, the solenoid cannot dump the excess quick enough, should knock occur, to control the knock. The knock that damages the motor is out of the range of human hearing, so just because you don't hear pinging doesn't mean its not there. The knock you do hear at times is not the knock that damages the engine. Not to mention the wonderful things the added stress to the tranny will do to it.