Wheel offset on a b6..

I currently have 18x8 aftermarket wheels wrapped in 235 rubber on a 2002 1.8 a4 with no suspension mods at this point.. was looking to do a wheel offset for a slighty wider stance.. the aftermarket wheels did help but i wouldnt mind a bit more.. i was lookin on ecstuning but wasnt sure what kind of limit i have without having any kind of rubbing issues.. i tryed searching but a had little luck with b6's.. suggestions??

This seems like it definitely should be in the new B6 thread up above because it pertains specifically to a B6

let me throw it in there then..