Re: 16" vs 17" Wheels and Tires
That's weird. It sound like the new tires/wheels combination is a smaller
Appears to be a 5-6mph difference (e.g. shows
> > >> 80, only really doing 74-75).
"Ironrod" <email@example.com> wrote in message
> You could do the old 1+ method, I think it went something like this, for
> every inch increase in rim diameter you add 10 to the width and subtract
> from the aspect ratio. Example, take a stock 16 inch rim with 225 by 60
> tires. i.e. R16 x 225 x 60. To go to a 17 inch rim but still maintain the
> same overall diameter you would replace your tires with R17 x 235 x 50's.
> This gives you a wider, lower profile tire with the approximate same
> diameter as the ones you just replaced, note the operative term wider,
> fender wells need to have enough room to accommodate the new tire.
> Everybody feel free to jump in here if I got this wrong
> <alfredB18@prodigy.net> wrote in message
>> Carl wrote:
>> > Not sure about 'stangs but in Jeeps we just buy a new speedometer drive
>> > gear. Also called a pinion speedometer drive gear. It's calibrated to
>> > tire size and gear ratio. IE: I had 33" tires and 4.10' gears in my
>> > so I needed a 32 (guess) tooth pinion speeedomete drive gear.
>> > HTH
>> > Carl
>> > "trainfan1" <firstname.lastname@example.org> wrote in message
>> > news:5JWdnUHN3sYlUSTenZ2dnUVZ_tWdnZ2d@usadatanet.net...
>> > > gjt wrote:
>> > >> Group:
>> > >>
>> > >> 1996 Mustang GT Convertible. Had factory 16" wheels and tires.
> Bought a
>> > >> set of the factory 17" GT/Cobra 10 spoke wheels and added new tires.
>> > >> the difference between the 16" versus the 17" wheels cause a
>> > >> in the speedometer? Appears to be a 5-6mph difference (e.g. shows
>> > >> 80, only really doing 74-75).
>> > >>
>> > >> How would one go about getting something like this re-calibrated?
>> > >>
>> > >> Thank you!
>> > >> gjt
>> A programming from a stealership or one of those programmers used in
>> OBD2 vehicles will do the job.