with about 420-430 rwhp, which is what a vortec on a newer stang , 3 valved engine should be at least that, and wide rubber...my guess is 11.8 @ 122.
Where are you located? i know there are many of shops that tune mustangs but there is one in huntington valley xxx, and they are good.
http://www.axceleratedmotorsports.com/