Need correct revs per mile please!

[Jteets75]

I got my sct tuner and need to adjust my revs per mile for tires and get the speedometer at the correct speed, the tires are 37x12.50R17, thanks!

[terryknight]

okay here we go again, you need the circumference in inches, then convert it to ft and then divide the distance (5280) by it. so assuming the the tires really is 37 inches in diameter and using 3.1415 as pi:

5280/((37 x 3.1415)/12) = 545.1 revolutions per miles

sorry if i came off pissy. it's not hard to do this conversion and i hope you know now or can reference this if you need to do it again

[Jteets75]

Originally Posted by terryknight

okay here we go again, you need the circumference in inches, then convert it to ft and then divide the distance (5280) by it. so assuming the the tires really is 37 inches in diameter and using 3.1415 as pi:

5280/((37 x 3.1415)/12) = 545.1 revolutions per miles

sorry if i came off pissy. it's not hard to do this conversion and i hope you know now or can reference this if you need to do it again

Sorry I'm on my iPhone and searched but it came up with nothing even close to what I wanted lol but thanks!

[CM250]

Originally Posted by Jteets75

I got my sct tuner and need to adjust my revs per mile for tires and get the speedometer at the correct speed, the tires are 37x12.50R17, thanks!

Hey man try out this website and see what you get.
Tire Size Calculator - tire & wheel plus sizing

I used their calculator for a variety of things. It will show difference between tires/wheels also.

[44magnum]

Also there can be differences between brands and models, best bet is to go to the brands website, its usually noted somewhere.