A bone stock Mustang GT (not a GT500) should be able to do 0-60mph in around 5.2 seconds. At least that's what all the tests I saw said. And my G-meter registered about 5.0 when all I had was CAI/tune and gears.
As far as the 0-100mph... I have a timeslip that says 7.0sec @ 98mph. Since the trap speed is an average of the last 60 feet (which means it's actually running faster than 98mph at the stripe), then it's safe to say I've run 0-100mph in 7 seconds. And my G-meter has shown 0-60mph in 3.0 seconds. I've compared the G-meter to timeslips at the track, and it's within a 0.10 sec in the 1/8-mile, so even the worst case would be 0-60mph in 3.1 sec.
Oh BTW, my local track had the 330-foot incremental mph listed on the timeslip for the first time this last week at the track. The best 330' incremental (with really bad air) was 4.70 @ 75mph. Not too bad for a 100-meter dash.