Sbak1320@aol.com wrote:
>
> It's a pretty simple formula to find a tires diameter.
>
> R/T tire 255/55/17: sec.width(255mm)x sidewall height .55(or 55% of
> sectional width)
> x2, divide this by 25.4 to convert to inches
> + 17'' (wheel dia.) =
> 28.04'' dia.
>
> 275/60/15; 275mm x.6 x2 divide by 25.4 + 15 = 27.99'' dia.
>
> 255/55/15; 255mm x .55 x2 divide by 25.4 + 15 = 26''.04
>
> To find the new effective ratio; tire dia. you're using now / tire
> you're going to use x gear ratio,
>
> example: 28.04''(R/T tire dia.) divided by 26.04'' (a
> 255/55/15) = 1.077
> 1.077 x 3.92 = 4.22 so your new
> effective ratio would be
> 4.22 instead of the original 3.92 w/ the
> original tires.
> see, math can be fun!
>
> Jon, has a wheel calculator on the DML homepage that will take all the work
> out of it, if you hate
> doing math :)
>
> SB
>
> <<<<<<< Ok cross check on this dia and numbers for
> ratios/gear/translation
> here..... Talk to like I am a five year old here. If you drop 2" in
> the rim, and add what slicks or drag radials it does who to the
> theoretical gear ratio???? Every one knows the R/T runs the 3.92, so
> what happens when I use the 15x8 with a given drag radial???? Does the
> higher side wall bring me back to the 3.92 side, and the low side wall
> drop me to the 3.55 side???? I am confused, and as Confucius say, 'Man
> with itchy butt shouldn't chew his finger nails.'>>>>>>>>>>>>>>
I tell you what's even easier, measure from the ground to the top peak
of the tire.
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:12:19 EDT