Originally posted by Kirby
It's not bad for your motor, unless your fuel system does not adjust fast enough or something. There are no ill effects of running low boost in first and then high boost in a diff gear (or any other 2 stage setup really). The only way this would be an issue is if your turbo went from like 10psi to 20 psi in a second (this won't happen as the turbo will need time to build the boost).

Well.. obviously you have never done it. I used to run 10lbs through 1st gear. Then hit the switch once in second gear. I would jump from 10 to 20lbs in an instant. Now.. if I were to do this I would be going from 10lbs to 27lbs. In my mind, its just a big strain on a motor that doesn't need to be there. You should be able to launch the car well enough on high boost that you don't need to switch boost levels.