275-40-17 with drop spindles
 

i have a 1972 pontiac lemans that has been lowered with 2in drop spindles and hotchkis lowering springs all around. my question is it possible to run a 275-40-17 on the front and 315-35-17 on the rear?

I believe that you cannot run that big of a tire you will destroy the spindle.

I don't think you'll be able to run enough backspacing to fit with drop spindle.

Usually, about 4.5" bs max with a drop spindle, before the wheel hits the tie rod. But measure to be sure.