Got this off another thread.
What do you think about this being a mod for the bypass valve on a supercharged model(LSJ).

Note: Front wheel drive platforms using the 2.0 Liter RPO (LNF) incorporate a charge air bypass valve supplemental vacuum tank. The purpose of the tank is to provide an instant source of vacuum to the bypass valve via the bypass solenoid (when it is commanded open by the ECM). This results in less pressure buildup under closed throttle conditions, thereby reducing compressor noise, surge and spool time.

 

people with ss sc just do the boost bypass mode which is the same thing but free and easy.( but i have heard harmfull)

 

its not needed at all...
its a turbo specific thing (and no the "bypass mod" is not comparable)