Contour Enthusiasts Group Archives Forums Modifications Wheels & Tires Tire size difference (affect speedo.)

I currently have 205/60/15 tires on. I just purchased a set of Blizzak tires and the size
are 205/65/15/ I was wondering if this will effect the speedometer or not.

Thanks

Not an expert... but I know that u will have a difference... but since u only increased the overall diameter by 5% of 205mm = 10mm I don't think that's a big difference.. comparing if u had now bought a set of 17" wheels....

HELP !!!! I know I am on the right track here... Can someone just back me up ???

Hey.. It's me again !!

Play around here and u'll see how the number change... and if u plug it in a 18" wheel u'll see a greater difference....

Try it out... nice script...
http://pw1.netcom.com/~sgalaba/mph.htm

Although I knoe how t calculate it, it's a long-winded explaination. But, a look right down this list shows this topic:
http://www.contour.org/cgi-ubb/ultimatebb.cgi?ubb=get_topic&f=31&t=001375

Miata calc, know it, love it.

Cool, Thanks!!!