I went from standard 13's to 195/45/15 on 7" wide rims, it's lowered on Spax dampers and Eibach springs but can't remember how much. Rear wheels had to be spaced about half inch to clear the spring caps (stub axle spaced, not wheel spacers), but this caused scrubbing on the rear nearside arch when giving it some on slightly bumpy roads. Why only one side I don't know! 6" wide and narrower tyres would perhaps avoid both problems, but I don't know as I've no experience.
With this size wheels and tyres the car felt slower and not as agile and nimble. But as I'd like 256mm front discs I'm going to compromise with 6x14, probably go with 185/50/14 as it's been mentioned more than once on here that this is pretty close to the radius of the standard 13's.