Select a size for your vehicle from the drop down and click the "Alternate Sizes" button to see a list of similar tire sizes.
You can then change the wheel size to see alternate sizes on a different diameter wheel.
Select a Size to Compare Prices on Available Tires
Porsche equips the 2005 911 Carrera 4S Coupe with a 225/40R18 front tire and a 295/30R18 rear tire. Click on the sizes for each tire to compare prices online.