What size torsion bars and what ride height in the front now? How much front end travel before the suspension limiters work?
I would lower the torsion bars to the bottom hole and see how much that helps your sixty foot times
My old ladder bar coil over Duster(3450Lbs. with me in it) started out with 175 lbs. springs, I switched to a set 150 and that helped, I should have tried a set of 130 Lbs. but I didn't
On your deal not knowing on how much weight is on the front and rear I would probably try a set of 140 Lbs. springs next