Here's how my car sits now
Front 18 X 8 ET20 235/40/18 Rear 18 X 9 ET22 265/35/18
next summer I'm going with a tad more aggressive set up with the wheels bellow in one of three configuration ( all 3 would fit without rubbing)
Square 18 X 9 ET25 245/40/18 with Spacers in the rear
or
Front 18 X 9 ET25 235/40/18 Rear 18 X 9 ET15 265/35/18
or
Front 18 X 9 ET25 235/40/18 Rear 18 X 10 ET35 265/35/18 (Most likely)