the point of twincharging and yes its done on the ecotec, go check out cobaltss.net if you want to see it, is because a low displacement motor, i.e. our 2.2s have trouble spooling a massive turbo, causing a major lag, what twincharging does is give you the low end power which helps with the lag, and also the roots blower is positive displacment which will help spool said turbo quicker. No you wont see the boost from the s/c at higher RPMs as it has a bypass valve that engages at a certain rpm, but your massive turbo will more than make up for it, the S/C just gets you into that power faster, eliminating the lag.
Edit: My Alero is a 3400 which has a bad headgasket, the car im referring to is actually my Balt, same engine, so im helping out with ecotecs. Most of what we can do with our engines you can do, plus you can use HPTuners, we cant, damn ECM
