i need a lil help. i have 2000 cobra R wheels on my ride. i replaced the ones the previous owner had burned to nothing. he had 245/45/18 all around. so thats what i bought. didnt think nothing of it till i kept feeling the passenger side front bangin the sway bar so i pulled it off and found that it was an 18x9.5 so i pulled the rest to check and yes 18x9 n 18x9.5. so now i need to know what can i run on the rear. the 245/45/18 on the fronts look fine but you can tell there is stretch on the rear. how big could i go? and thanks for any input.