I had the same problem, lol. Most goat owners are M6 owners and don't know about the computer BS of the automatic. The only way you can smoke the tires while holding down the brake (aka burnout at a dragstrip) is to have your computer reprogrammed. Stock will not let the tires break free, GM's way of keeping people from frying rotors and brakes is my guess. The car's ass end just squats down as you hammer on the gas, it revs up to like 800 rpms, and nothing happens.
Once you get a dyno tune that disables torque management, top speed governor, etc., you'll be able to light those babies up till the rims are glowing. Or, you can do what I did and go to www.autoanything.com
or another similar car mod website and buy the Diablosport Predator handheld tuner model number U7191 (for the LS2, doesn't matter what vehicle it's in) and you'll be set.
I bought mine last summer when I got my '06 IBM A4 and it cost $400. It may have gone down a bit but most of the handheld tuners run between 350 and 400. You'll also have snap you back in the seat higher rpm shift points, and an error code reader (which I've used twice to find out my gas cap wasn't on tight enough). It's worth the money.
You can choose between a pump gas tune and a 93 octane only tune, which is more aggressive, with more hp and torque, that's what I run, but depending on where you live, you might not be able to get 93 octane. That's why all your new high end sports cars have recommended octane ratings of 91 OR higher. I guess you can get 91 octane anywhere. Hope this helps.