The Standard gear is either a 3:46and I think it was a 3:08.
I have the LSD with 3:46 opition installed by BDR,I also have the Roush 427SR/TW motor with the Tremec 600.
85 is about 2700rpm in 5th.
The rear gearing will depend on your transmission final ratio and your motor hp and tq to get a good combo.
I am happy with mine the way it is set up and for my needs.
Marc