Read my first post.

A CAI will effect a turbo car, yes. But at higher boost the pressure increase causes a temperature rise that is so much higher than ambient it overrides the temp difference the CAI gives you ... which is why high boost requires an intercooler.

Maybe numbers will make more sense. Compare 20 and 40, pretty big difference right? 100% Now add 200 to both of them. Now the difference isn't nearly as great. 10%

All of this is practically a moot point since humidity has just as big of an effect (if not greater) than temps do. Getting a CAI for a turbo car certainly won't hurt anything.