You should be able to run them without any problems if you have the correct tires. I have 18s on mine with a 245/45 tires I think. Don't know if it's 225, but anyways. It barely passes by 5mm. Your tires are too thick so in between 215/50-225/45 is enough to clear it for you.
Basic info on tires:
the triple digit number you find on tires, Ex. 225/xx 215/xx refers to the width of the tire.
The double digit after the first set, Ex. 212/55, 225/45 refers to the thickness of the tire wall (Sidewall). The spacing between the outer rim of your wheel and the outer surface of your tire. The higher the number, the thicker is, lower, the thinner it is. Hope that clarifies it a bit for you.
Here's a link that goes in depth on tire sizes, the meaning behind the numbers, letters, and dimensions.
http://www.tirerack.com/tires/tirete....jsp?techid=46