I thought you would have been in the low 14's/high 13's with that setup. First thing I noticed in that list was the gearing like everyone has said. Has the car been tuned? What's the car weigh? The heads are definitely killing potential.
As a side note, that's a clean looking car.
1995 Mustang GT
1999 F150 Lariat 4x4
Soon to come: 393 stroker
351w bored .030, Probe Industries forged internals, Trickflow 205's, FTI custom cam, Trickflow R 90mm intake, Accufab 90mm TB, FRPP 42lb injectors, 1 3/4" custom Accufab LT's, 3" exhaust, MS2