17's or 18's?

[nick01A4]

i have a B5 A4 i want the performance of a 17 but the look of 18's (or 19's)or would it be that much difference in power and ride. Also at what point do you have to recalibrate the speedometor for accuracy?

[VMRWheels]

As long as you keep the tire the correct size when moving up rim diameter you wont be off much on the speedo.

-Charles@VMRWheels

[Doc@tirerack]

Stock tire diameter is approx. 25.0". You can do the following and stay within 0.5" of that number;

225/45-17
225/40-18
235/35-18