Posted: Jan 29 2007 at 11:18pm | IP Logged

If you want them to be as close to accurate as possible.  Or you can figure out the difference, and just drive slower.

http://www.tyres1.com/calculators.html 

Just put in the stock diameter, the new diameter, and speed say 55 mph.  It will show you what you're actually doing when you speedo says 55 with the bigger tire.

Posted: Mar 05 2007 at 9:15pm | IP Logged

..

Here is a tire size and speed calculator.

http://www.discounttire.com/dtcs/infoTireMath.dos

And welcome Bob..

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