Yeah, as long as you're keeping the overall diameter of your tires the same you shouldn't have to mess around with anything else as long as you don't get tires and wheels that are so wide they will rub the fender walls.
To figure out the size you should get you can you can compute the exact specifications. While there are some rule of thumb things which you might see: Add 10 to Width; Subtract 10 from Aspect Ratio here is how you can compute the exact diameter of your tire (i found this from tirerack.com somewhere in their plus sizing help area)
Tire Width (205mm) : 205 / 25.4 = Width in Inches (8.070866) Aspect Ratio(55): (55/100) * Width = Height of 1 Sidewall (4.438976) Total Sidewall Height: 1 Sidewall*2 = (8.877953) Rim Diameter(16):
On Tirerack.com they suggest 215-45-17 for 17 inch rims but it is closer to stock to pick up the 225's and be slightly larger than slightly smaller.
I'm not sure how wide you can go with our car but 215-35-19's should work. I don't know anyone personally who's running 19's to ask. I hope that helps and wasn't something that you already knew.
