I ran an 86 cutlass at 2835# Big chevy powered, that had a 4 link and a 12 bolt with billet caps, studs, Mark williams moly spool with pro gears and an aluminum cover pre loader type that I ran 8.41 ET at 164 MPH for over 600 passes, replacing the gears every 200 passes no matter what they looked like. The new owner runs less power and will likely never have a problem with it running 9.80ET mouse power. I would not try to go a lot faster with a bunch more power and expect to run this long with out trouble. I think that a ladder bar suspension tries to bend the axle tubes more than a 4 link does, but do not have first hand exp. going faster than 8.5s with ladder bars at any weight.
Hope this gives you a measuring stick to go by.
Bruce