is there a chart that showes tire sizes/equivalent examp-metric size for 31-35 inch tires thanks

 

Search is your friend

 

It changes a lot based on the width and aspect ratio. I've noticed a lot of guys on jeep/truck forums don't understand how it works and think a 305 is a 33, 315 is a 35, etc. This is NOT correct, don't let anybody tell you it is. You can find the equivalent size in imperial units like this:

Width: divide first number (215,275,315, etc) by 25.4.

Height: divide first number (215,275,315, etc) by 25.4, then multiply by the second number (40,75, etc), then multiply by two and add your rim diameter

 

Your wrong on the height conversion!!

((((235/25.4)*70)*2)+16) is 1311.2

The correct way is

((235*70)*2/2550)+16 = 28.9

A 235/70-16 tire is 28.9in tall not 1311

 

Do a Google for "tire size Calculator" There are several on the internet- I think I use one from miata.net

 

http://lmgtfy.com/?q=tire+size+conversion

 

It's a ratio, so obviously you use 0.7 not 70.

Also, your divisor should be 2540 not 2550

 

Here is another site I use...

http://www.onlineconversion.com/tire...conversion.htm