Ahhh yes, the majestic, elusive pothole that only areas that snow seem to have...
Anyway to cut the sarcasm short, "flushness" won't result in your wheel/tire slamming into your fender, bad fitment and suspension setup will. My setup is flush, with a decent tire, and I have no rubbing/etc. but no clue what I'm talking about either so enough about me.
To answer your Q: if you plan on going with the 18x10/11 GTC combo I would have originally suggested a 275/40 and 305/35 combo... however, since you don't want to listen to advice and want to run oversized flares on an undersized offset (including the spacers), I'd recommend you get the largest, widest tire you can fit on a 10"/11" wheel. So, something along the lines of a 305/35 in front and a 335/30 in the rear.
|