I know this really isn't a suspension issue but this is about the closest section I could see for this question.

I believe my speedo/odometer issue in that my speedo displays about 5MPH faster than I'm actually going at 60MPH (speedo shows going 60MPH but GPS shows I'm going 55MPH) is common to others also. (This also puts an extra 50 miles on the Odometer for ever 1000 miles traveled).

So I'm thinking of trying tires that are a little larger than my stock tires (on 15" rims). I've been looking at some Bridgestone Potenza RE 960AN Pole Pos 205/65 R15. These tires have an overall diameter of 25.5" (7.9" tread width) where as the stock Continentals are 24" in diameter with a 7.2" tread width.

So what I'm wanting to know is, has anyone else ever gone to this much of a larger tire over the stock tire size? I'm concerned if there are any size issues withing the wheel well for this size tire.

So do anyone have any thoughts on this?

Thanks,
Mike...

 

I haven't heard of anyone increasing tire diameter by 1.5" to address such a speed and distance accuracy issue, but then I haven't been reading here for very long. There should be enough room for a 205 width, but the tire size you're considering is quite a bit heavier (with a significantly higher maximum load) than your OEM size. A 195/65/15 in the same tire would be 3# per tire lighter than the 205/65/15, but both sizes are molded to fit a 6" wide rim better.

I'm biased against tall tires anyway, so I think I'd just make my own mental adjustments to the optimistic reading rather than mount tall tires to compensate.

There is a Tires, Wheels, and Brakes forum.

 

here: https://www.northamericanmotoring.co...6-success.html

 

Thanks for the link. I was just going to move this posting to that forum (when Jim mentioned it) since I missed it when I was looking for a place to post this. But that link brings up the same discussion, so I'll continue there.

Thank you both for responding.

Mike...

 

I just calculated we would need 235/35-20 to make up that much difference (starting from 205/45/17). That is rediculous!

http://www.tacomaworld.com/forum/tirecalc.php

here is a little better calculator.