i think with 235's it will rub a fair bit. you need 225's.
dont get 19's though, they just look too big for the car, and are a kill unsprung weight, so they will make it handle worse, and accelerate slower, and give a REaLLY harsh ride.
personally, i think the ride of 18's is too harsh, i can only imagine 19's will be horrible!
17's all the way for me!