I was talking with George Howard on Saturday at Huntsville (race promoter extraordinaire, owns Montgomery, Huntsville, Bama Dragway, put on the $50k 10.5 race, etc) and he ran a new Z06 at Montgomery a few weeks back. Said he tried running with traction control off, blew the tires. Left in 2nd gear and ran an 11.78 through the quarter. He didn't tell me the mph (and I forgot to ask).
He said the car is a beast. I'm not sure what they are supposed to run stock but 11.78 is cookin!!
And for any doubters, if you know George, he is a reputable man of his word.