Waiting for OP's reply if the mustang had more mods than we all thought...
The new 5.0 mustangs ('11 and up) are fast. The mustang was basically head to head with the M3 when tested by Motortrend. Take a look at the 1/4 mile race vid. Basically tied every time, but the mustang had a slight edge at the end of the day and won by 0.1 of a second. 12.7 @ 111.6 MPH compared to 12.8 @ 110.9 MPH. Here's the vid:
In the track, the mustang was also head to head with the M3. After Randy Pobst drove both cars at the track, it only came down with the M3 winning by less than 1/10 of a second. M3's time being 1:27.67 compared to the mustang's 1:27.76. That's a 0.09 sec difference in lap time! Here's the vid:
That Cayote engine is something. Ford did something right with the motor this time round.