what backspacing should I run on 33x12.5x15 tires with balljoint spacers up front on a 1995 4runner.

 

probly 3.75 you might have to do a little cutting, hammering and griding no matter what bs you have if all you have is bj spacers

 

well would cranking the torsion bars help out?

 

yeah but you will have less flex, a bad ride, and will need to align it after. i would strongly reccomend hitting and or cuttin over a tbar crank ive been there and my ifs went to crap soon after
just my opinion but to answer your question yes it would help

 

You will need wheels with 4-3.75" backspacing. You will need to do trimming in order to fit those wide tires. They won't fit right in...