Content Wrapper

[JohnWB]

Quote: Originally Posted by minicabrio (original)

What do you base that on? Have you driven different sizes back to back on the same car?

Choosing the 215/45 over the standard 205/45 will increase the radius of the wheel and tyre by 1.46% - this means that at an indicated 70mph you'll actually be doing 71.02mph.

If instead you choose the 215/40 over the standard 205/45, you will actually reduce the radius of the wheel and tyre by -2.03%. This means that at an indicated 70mph, you'll actually be doing 68.58mph.

I run the 215/40's, the grip is much improved over standard, but then it would be running non-runflats, handling is much improved, but then again it would be, and again comfort is also improved.

Using you own figures, the difference between the standard MINI 17 inch tyre & the 215/45 is 1.46%, whereas the diference for the 215/40 is 2.03% which is further away form the optimal size as detrmined by MINI
The difference is not very much but the lower sidewall hight tends to give a stiffer ride and slightly less roll
Both sizes are much better than the runflats and the majority of people have tended to go for the 215