How Far Out Is My Speedo Going To Be?

[iwontarolla]

Hey guys,

Just started to drive my ke70 and I'm alittle worried my speedos out. I'm running 14x8's with 195/55-14. I can't remember what stock is but it's Lot bigger I think. I have a random diff center and i have never figured out ratios, I know that's no help. But is it more likey it will be reading faster than I'm actually going?

Thanks chris

[rian]

I just did a few very rough calculations, the rolling diameter of the 195/55/r14 was a tiny bit smaller than the rolling diameter of stock wheels (I think i have 175/70/r13 on my stock wheels?) so your speedo should read a bit faster. You should do the calculations for your self to make sure, or use this program:

 

http://www.willtheyfit.com/

 

Enter your new and old wheel/tyre specs and it should spit out speedo error, speed at 50km/h, speed at 100km/h etc.

[19914afc]

You will need to know diff ratio before you worry about what size tyres you have.

[towe001]

Or if you have a android phone with gps then download

https://play.google.com/store/apps/details?id=com.binarytoys.speedometer

 

That way you don't have to figure out diff ratios, tires sizes and other mathematical formulas.