How well does 225/40/18 protect your rims? (archive)

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Posted by eom on May 03, 2000 at 02:30:28:

In Reply to: Re: Kev: Why are you using 225 instead of 235 posted by Kev on May 02, 2000 at 08:18:04:

(posted from: ts010d11.sjc-ca.concentric.net (206.173.235.215))

Here's a sample calculation of wheel diameter:

For example: for a 195-65-15 tire:
195 * .65 = 126.75 mm

126.75 mm / 25.4 mm/in = 4.99 in

4.99 in * 2 (top and bottom of tire) = 9.98 in

9.98 in + 15 in (wheel size) = 24.98 in.

205/55/16 = 24.87 in
225/50/16 = 24.86 in

**********************************
Sport package wheels on 328ci
Front - 225/45/17 - 24.97 in
Rear - 245/40/17 - 24.71 in

225/40/18 - 25.09 - you're RIGHT!
235/40/18 - 25.40

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