As others have said torsion isn't and shouldn't be an issue. Go into a store and take a look at the stands that tens of thousands of tanks are successfully being used on. The first time I seriously looked at the construction it floored me and made me realize how insanely overbuilt my stand is.Conservatively vertical load capacity is 36,000 lbs. realistically 58,000lbs.
One 30" 2x4 has the vertical strength to hold up a truck. Load isnt the issue with these stands, torsion is.
danged if I can figure out torsion resistance of this stand without a phd in material physics.