1/4 mile times are all depenedent on the launch...if the launch is shit, the time will suffer, regardless of how much power you have.
I stick on a set of slicks and manage to cut a 1.7 60ft time at Shakeys or Santa Pod (or a prepped track of some sort).
As a rough guide, every 10th taken of the 60ft time is 2 10ths on the 1/4 mile.
So I did a 13.1 with a 2.3 60ft time.
In theory, with the same power output and only a 1.7 60ft time, it would drop to 11.9 seconds on the 1/4, and that's just with the launch.