'09 and earlier - 3,920lbs w/ shaker 1000(damn near all of them came with it)
3,850lbs without
'10 - 3,940lbs w/ shaker 1000(same, good luck finding one without it)
3,870lbs without
'11 SVTPP - 3,750lbs
odds are that you bought the car off the lot with the 1000, or you ordered it without. if you have it, that's a 200lb weight difference. and off the nose.
you can cut this a number of ways, but the fact is that the '11s have 10 more HP stock, have 100 to 200lbs less weight, off the nose, and have much better tires. same driver, same conditions, the 2011 SVTPP will be consistently faster, it's not debatable.
...do the same to a 2011 and it's still 100 to 200lbs lighter:shrug:
you forgot that they have the better intercooler as well which means on the street they will have a lot less heat soak.