i have 1.75" of lift and can fit 265/75R16 or 32" tire with add-a-leaf (highly recommend this over shackle) and torsion twist
a rule of thumb on the tracs and any torsion bar IFS expo, trac, ranger, etc. is not over 2" of un-settled twist on 4X4 cause as hugh said CV axles go kaboom, and...