Need help calculating new tire pressure

I need some help understanding how much pressure I should have in my tires.

Original Tires: 265/70R16
GAWR Front: 2910lb @35psi
GAWR Rear: 3280lb @ 35psi
New Tires: 235/85R16
Max Weight 3042lb @ 80psi

I thought the formula was,
(weight_old_tire - weight_new_tire) / psi_new_tire = change_in_pressure_from_stock

e.g. front (2910 - 3042) / 80 = -1.65 psi ???

 

2011 Dbl Cab short bed TRD Offroad 285/75/17 BFG KO2's "E" Load rated I run them at 25psi with no cargo. At 25 the outer tread blocks are in just slightly less contact than the rest of the tread (compensates for cornering) and they have been wearing very well. At 23psi the tread has even contact across the entire face of the tire.

 

I didn't know about that calculator. The new size works out to "Load Capacity: 2205 lbs. @ 50 psi." which is around 2,000 lbs higher than stock. I don't think that 50psi is correct

 

I run 235/85/16 on my 6800lbs without the plow GMC K3500srw OBS plow truck at 40psi.

 

Have you had them long enough to show any wear? Is the wear even between the middle and side tread?

 

Wearing even across the tread on all fours.

 

Try this one?