What are the biggest rims and tires can i put on my 86' brat w/ out lifting it?

Been covered - use the search.

.. First normal question, do you mind cutting and hammering, trimming and bashing? If not, 27's should fit. maybe bigger. If you don't want to beat it up, then 25's will fit. Also depends on the offset.. If you just goto the Offroad section you'll see a "sticky" with the same question you ask.