? on tire sizes...

[Blackin]

I never did get the hang of that formula thing, but I imagine one of you is crafty with it...

What's the difference(Height and Width) between:

285/70r16
275/60r16

[stlblues]

285 will of course be taller, not sure exactly how much but not a huge difference. the 60 will be about an inch wider than the 70. Don't have the exact formula on had. Just slap on some 305/70/20s.

[titanQ]

The first number is the width
The second is the height
The third is the rim size

[d0va]

285/70r16=31.7" x 11.2"
275/60r16=29" x 10.8"

try this site http://http://www.raingler.com/tech/metricTire.asp
coverts it to metric ez to read

[gr8titan]

Originally Posted by Blackin

I never did get the hang of that formula thing, but I imagine one of you is crafty with it...

What's the difference(Height and Width) between:

285/70r16
275/60r16

Formula to get OD (outside diameter) or height of a given tire:
width (mm) x aspect ratio X 2 plus the wheel diameter in inches
23.4

First # is width in mm, 2nd # is profie aspect ratio in percent, 3rd # is wheel diameter in inches
Example on first tire:
1. (width) 285mm multiplied by 0.7 (this is decimal equivalent of 70% profile) equals 199.5mm
2. divide 195.5mm by 23.4 equals 8.52 in. (to convert sidewall thickness from MM to IN.)
3. multiply 8.52 by 2 equals 17.05 in ( to get total sidewall thickness of tire in inches)
4. add 17.05 in to (wheel diameter) 16 in EQUALS 33.05 inches OD

Using this formula, the 2nd tire is only 30.10 inches in diameter which is smaller than the first tire.

Mathematically, 285 tire is only 10mm (or 0.427 inch) wider than 275 tire.

Hope this helps

[konigfritz]

Thanks for the formula!!