17" Tyre Sizes

[jackamp]

I have 225/45/Z17 's fitted on my Passat V5. What are the cosequences in fitting another size, like 225/50 's or 55's. Why all the different sizes ?

[xenon]

I have 225/45/Z17 's fitted on my Passat V5. What are the cosequences in fitting another size, like 225/50 's or 55's. Why all the different sizes ?
The 50's will make the tyre 23 mm bigger in diameter and 55's 45 mm in diameter. It is not recommended to do this.

[Corb2000]

Best to use an online tyre calculator to compare the overall diameter of different tyre sizes;

http://www.alloywheels.com/tyrecalc.asp

This will show you the difference in real speed caused by changing the original tyres, really easy to use and soon demonstrates the allowable combinations. It also checks tyre sizes against wheel sizes.

55 and 50 ratio tyres are for economy and comfort whereas the lower 45 and 40 ratios allow wider tyres to be fitted and increase the area of the tyre in contact with the road to give more grip.