Will 18" alloys with 205 45R 18 tires hurt
 

Hi there all you Mazda 3 crazies. My name is Nishantha and greetings from Sri Lanka. I have a 2011 1.6L Mazda 3 with triptronic transmission. It came with 205 55R 16" wheels. I've seen more sportier wheels on Mazda 3s and want to change to 205 45R 18" wheels. I read some advice on changes done so as to alter less than 3% of the circumference was OK, especially for the speedometer readings to be accurate. How will it affect the suspension in my version of the Mazda 3? Can there be other issues? Please advice.