Hey Gav,
If your talking about a total lift of almost 3", i would guess it's probably either 225/75/15 or 30's.
I'm comfortably running 31 MT's with no rubbin and my shed (vitara) has procomp springs with b4v spacers and a 2" body lift.
Having said all this i am no expert in these matters, so i expect to be corrected shortly.
Phil