Put the Duster on the DYNO.
Best so far 6.62 my 60' are pretty shitty usually around a 1.51. But they are consistently shitty. I need to do some suspension work. Im running a 10.5 x 28 slick. A better gear may help a little im still running a 4.10, but its nice to be able to run both the 1/4 and 1/8 without having to switch.