Achieving 12's is no huge feat with a great launch. A GT with the potential of running a 13.8 with a 2.0sec 60ft goes to a 13 flat car with a 1.6-1.7sec 60ft.
The speed density fox cars have run 12's with the stock heads/cam/intake as well. Headers, H pipe, dumps, 4.10s, 4 banger springs, electric fan, iced intake, CAI, drag radials or ET streets, and you're knockin on the 12 second door. It's just about what you want to sacrifice for it. A 1.6 60ft will drop nearly a full second off the best run with a 2.0 60ft time.
That being said, the 12sec stock engined 5.0 or 4.6 is going to get killed on the freeway. By any car trapping 105mph+
