You cannot turn off the supercharger, but you can turn off the boost. If the supercharger has an electronic wastegate installed, it'll be spinning but the extra pressure will be blown off into the atmosphere.

 

305 Nitto 555R on the 9.5" rear wheel? Would be sweet, but everything I am seeing says a 305 needs at least a 10" wheel. Is anyone running a 305 on the stock Performance Pkg. rear wheel?

 

305 555R on 20x11 Forgestar F14's for a visual reference. As you can see, the tire goes all the way out to the edge of these wheels. You might be able to get the tire on there, but I wouldn't expect the tire to perform like it would on an 11" rim like those on my car in the picture.