I have checked the list from Maxis that Airdale gave in post above here.
It prooved to be made with the formula for Diagonal tires and calculated from the B-load ( 35 psi) tire , though its a radial tire there.
Calculated back the first tire, and asume the others are done about the same.
So advice is to not use this list , it leads to to low pressures for the load , or the other way around to high loadcapacity for the same pressure.
Even a list made with the power in the formula that is used in America for LT tires of 0.7 is to low . Europe calculates for all tires with power 0.8.
The higher the power the lower the loadcapacity for the pressure.
X to the power 1 ( X^1 notated mostly) is X, X^2=X times X so square.
X^0,5 means rootX.
I constructed my own universal formula from wich the others can be made by filling in the right power and construction load ( Lc'. If power is 1 and Lc=5% you have the formula presented by an American IR J.C.Daws for LT tires.
I made pressure/loadcapacity lists with power 0,95 ( so almost 1) and Lc depending on Pr ( referencepressure is not the maximum pressure,D-load 65 psi) and to my opinion this comes closest to the ever to be constructed ideal formula for all kind of tires.
To be found in next map on my skydrive.
But think I already made a topic about it on this forum so will search it back and give the link to that.
EDIT: here the link to the topic