Here is a fair shot at six C6 Z06s.
Swowing is
S is for stock
T is for after our 1st pass of tune
TW is if we then tweaked the tune.

This shows for best performance after the main tune is done and PCM does it's relearn then one more tune cyle is done to tweak what needs it.

All values were gotten from using a Ease OBD-II scanner in GMLAN mode and we have one cross check after tuning where Z06 owner used a load bearing dyno that was local to us.

Values when scanning were done are UNCORRECTED

Notice Rob's results, you see a loss in performance after tweak was done he forced the muffler damper to stay open all the time

Also Steve added that Halltech aircleaner and so called Aircharger and no real gains from it.