Originally Posted by sc00by4life
You're right! For some reason I kept thinking they were 18x8.5 +48.
Its a difference of 3-4mm at the inside of the wheel, I'm not doubting that the wheel clears stock suspension - but when you run larger tires, that gap can easily be filled up.
Yeah a wider tire would decrease the clearance a bit. This is pretty rough, but say you ran a 265 tire on the 18X9 wheel compared to the 245 tire on the 8.5" STI wheel, your tire is getting 20mm wider but the wheel is only getting 13mm wider. Divide the difference by two and you'd probably get about 4mm more bulge on the tire, so on the inside it would bring the clearance to about the same as the stock STI.
After all my research this seems like the best wheel fitment in terms of being as flush as possible without requiring fender mods on the 11+WRX, unfortunately finding 5X100 wheels in this configuration is tough. This size would probably even work well on earlier models to reduce the amount of fender work needed in comparison to something like an 18X9.5 +38 (which sticks out 13mm further).