I owned a 2012 gt automatic
I owned a 2012 gt automatic convertible, took it to a test and tune on a not perfect day and laid down numbers like @ bracket car. 13.53 to 13.59 @ 106. mph. Street tires warmed up. With a stock automatic, you cant load the wheels enough to 60 foot well. tires want to break loose at 1700 rpms on the brakes and even though the auto has a steep first gear launch, the motor just does not make huge low end torque to achieve real fast short times with stock 3.15 gears.
I traded that car for a 2014 gt track pack car and all i can say is there is a world of difference in these two cars. The stick car gives you the ability to launch wherever you want and even though the first gear ratio in the stick tranny is less...3.66 to auto 4.12 first gear.... the stick car with 3.73 gears explodes off the line and hops a bit as well. Second gear brings added bouncing as well as tire burning, and third gear provides ample chirp under the right conditions. i think Ford should have used a steeper third gear ratio in the 6 speed...it drops off a bit out of second and in reality is a little to close to 4th in gear ratio...
While i have not had the 14 to the track to test times, i am a firm beleiver that the optimal combo for these cars would be a well tuned auto by someone like lund or evoltion performance, with the right gears, 3.55 or 3.73. Throw in a converter to aid the stall and you would be in bracket heaven. I cant, and I dont beleve most drivers cant drive the stick as fast as these newer automatics built like beasts can perform. Too bad ford never offered the good gears in automatic GT. that was a mistake. 3.55 or 3.73 in an auto would be the cats ass.
Just my 2 cents