Superchargers gettin put on right now.. who will I beat?

With that kind of power increase, it'll take a while for you to relearn your car's power curve. Theoretically, you should be able to take stock LS1's no problem. Although, dont ever get it in your head that you can beat em all. If you manage closer to the 385 range, you can stand a good chance against an 03 cobra. This is if all you want to do is high speed racing. For 1/4 mile racing, a car with much less hp can beat a car that is much more powerful. There's far too many factors involved.

HP and TQ don't mean squat if you can't put it down to the ground!

are you getting injectors ,gears