Go to
www.tirereack.com and plug in your car. They will have the exact fitment and recommended wheels tires for your car including going down in size. In my case I had 228 I m sport non m sport brakes and so I could put 16 inch wheel with 205/55/16 blizzak ws80 on it.
Gil@tirerack.com email him....He helped me last time with my 128I coupe. Just got my setup delivered 2 days from online order up here to canada tire rack is flawless!