they dont require a flash when upgrading I have the GM instructions right in front of me .

GM stage kit instructions for stage1 to stage2 upgrade PAGE 8 :

IF YOU HAVE ******NOT****** PREVIOUSLY INSTALLED THE STAGE:1 SUPERCHARGER UPGRADE KIT YOU MUST PERFORM THE FOLLOWING :
YOUR VEHICLE MUST BE TAKEN TO YOUR GM DEALER TO HAVE THE NEW CALIBRATION FLASHED TO YOUR ECM. YOU WILL ASK FOR YOUR CALIBRATION BY PART NUMBER DEPENDING ON WHICH VEHICLE YOU HAVE INSTALLED THE SUPERCHARGER UPGRADE KIT ON
12607644 CALIBRATION DATA FILE -2005 CHEVY COBALT SS
12607645 CALIBRATION DATA FILE -2006 CHEVY COBALT SS

now guess what the stage one calibration file part numbers are

12607644 CALIBRATION DATA FILE -2005 CHEVY COBALT SS
12607645 CALIBRATION DATA FILE -2006 CHEVY COBALT SS

I have stage one with a used stage2 pulley and hub, my car runs perfect , i really have no clue as to why people would be so confused about this .

 

Yup i've been told by everybody i've talked to that they are the same exact tune....and just out of curiousity, how much could you get the stage2 kit at your cost??

 

hmmm. this makes me wonder wtf they did to my car then. because it ran like absolute garbage with the stage 1 and smaller pulley. KR was higher and my AFR was higher. sounds like they might have botched my stage 1 tune?

and if this is so, they need to quit ripping people off by charging for a "recalibration" in the stage 1 to stage 2 upgrade kit