I have a 2012 BMW Z4 35IS. tires are low profile 225/35 ZR 19 & 255/30 ZR 19. I have bent two rims and bubbled one tire in slight chuck holes. These hazards are tough to avoid at higher seeds around corners. I am going to be taking a trip and I want more tire between the rim and road. What size can I convert to including going to smaller rims?