Do not go 225-45-18s. It will definitely rub with your +43 rim if your car is lowered. You will be OK with 225-40-18s. If you want to have a larger sidewall, you can run either 215-45-18s or 235-40-18s. Either of these sizes would match the stock rolling diameter almost perfectly. Go 215-45-18 if you want to make sure that you do not rub.