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MadMax
11-06-2008, 07:09 PM
OK, math question for you big brains out there...

My Yaris has 215/45ZR17 tires on it, and stock tires are 175/65R14s. I know my tires are wider and have a lower profile than the stock ones; but they are also taller and as such, how much is my odometer/speedometer off?

Sorry, but I can't stand, and suck at, math! :iono:

Cheers! M2

CASTREX
11-06-2008, 07:11 PM
Here you go: http://www.1010tires.com/TireSizeCalculator.asp?action=submit&reset=yes

nemelek
11-06-2008, 08:51 PM
Take a trip on the highway. Using the highway mile markers and set the trip odometer to 0.0 as you cross the first marker. Travel 10 highway miles and note the odometer reading. Do this twice. Since your tires are taller your recorded miles will be less than the actual miles traveled. If you only record 9.5 miles for each 10 miles traveled than your odometer is about 5% slow. When figuring gas mileage add 5% to your miles. If your odometer shows 300 miles you have actually traveled 316 miles. Assuming your speedometer and odometer are in sync, your speedometer is also 5% slow. If your speedometer shows 95mph you are actually traveling 100mph.