brooklyn86

Really? So when driving normally (i.e. not aggressively), you don't hear the whine all that much? No noticeable sounds from within the cabin vs stock when just cruising?

NWS4Guy

No, the SC will only whine when under load, and the ECU will have the bypass valve open and bleeding boost unless it's needed - boost is on 100% of the time, since it's a mechanical forced induction, controlled by the pulley running of the engine crank pulley. Under light to normal accel, there is very little boost happening, usually only enough to bring it to equilibrium rather than having a vaccum like a normally aspirated engine has. Once you get past 40-50% throttle is there load to make the SC work and produce the whine.