Just depends if you want your tires to tuck inside the fender or not. Im on coils and at first I was going by what others were telling me that they would fit and blah blah, I tried the driver front first and the fender crumpled when I lowered the car off the jack, because the lip of the fender hit the center of the tire tread. After I had my new fender on, I took my own measurements. (and sold the 18x9.5 et35)
At factory camber, for a perfect tuck: (225/235 tire)
18x8 ET35
18x8.5 ET42
18x9 ET 47
That is all the wheel widths I have tested. Others may argue what I said, which is fine. I know those measurements to work.
You COULD potentially run those wheels if you get the wider Seibon front fenders and dial in some negative camber.