I just picked up a set of 18" A8 wheels for my 200TQ20v. Right now, they have 245/45R18 tires installed, they are too tall for the 200. Should I use 235/40 or 245/40 tires on them? What fits best? They have an offset of 48 mm, so I have to use spacers anyway, and can get spacers to "match" with the tire width. -- Regards, ES