this is a newb question but it is tire specific. i know the original width of the advans is 235 and that goes on an 8" wide wheel. im going with 18x8.5. is 235 still wide enough to cover the 8.5 or do i need to go with 245's. i dont want any rubbing of course. tire gurus let me know.

also what is a better tire performance/wear wise: Kumho Ecsta MX or
toyo proxes 4I

The stock 235's will fit wheels 7.50 to 9.00" wide. You should be just fine running that on an 8.5" wheel

With regards to rubbing issues, I am runnng 255/40 Nittos and have now problems with clearance. I run these for AutoXs and daily use, again no problems.

I even know a guy who ran 275/40s on his Evo at AutoXs