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How do you find the hight of a tire in inches (other then just measuring it). My tires are 245/60/15 what would the hight of them be?

[brainsboy]

about 26.57"

http://www.sstire.com/tireheights.html

[segge]

Originally Posted by brainsboy

about 26.57"

http://www.sstire.com/tireheights.html

Thanks saved that site to my favorites.

[bracketeer]

There is a calculator here.

[M&M CUSTOM]

The links are fine if you have access to the internet to check out a set of tires when you are in front of your computer.

A calculator or even a pencil and paper can be used this way.

Metric size tires can be converted like so:
Using your stated tire size 245/60/15
245 millimeters divided by 25.4 millieters per inch equals 9.645669, just round it to 9.65 for simplicity.
Multiply the 9.65 inches tread width times your "60" sidewall aspect ratio 9.65 times .60 equals 5.79 inches.
Multiply the sidewall measurement of 5.79 inches times 2, as you have that much tire above AND below the rim and you get 11.58 inches.
Add your sidewall measurements and your wheel size of 15 inches, and you get a tire diameter measurement of 26.58 inches.

Just remember that not all tire manufacturers sizes are completely accurate as to what the tire will actually measure, and this also changes when the tire is over or under inflated, and this also does not take into consideration vehicle weight either. All of these are unknown variables and cannot be accurately compensated for.

[Max Keith]

The most accurate way to find your tires actuall height is still with a measuring tape. And more accurate than chats.
Two tires of the same advertised dimensions doesnt guarentee they are the same height. They could easily be off as much as 1/2 inch or more. Factors here include materials and compounds used in production, temps of the tire when it came out of the mold, how long it maintained those temps, and how it was stored after production, and after shipping and setting on a rack waiting for mounting. Inflation pressures also play a part in a tires diameter.

The most accurate way to find your tires diameter is to measure the circumferance of the tire around the middle of the tread, while inflated to the desired running pressure. Divide that circumferance by pi, or 3.1416, or however far you want to carry out pi.
And dont assume that just because you have a "matched" set of tires, that both are going to be the same diameter as well.
In stock car racing, altering the circumferance of a tire, or rollout, is a trick used to make the car handle better.
The difference in the rollout between the left side and right side tire is called Stagger..
To alter the rollout in a tire, the trick is pumping the pressure up as much as 50 psi in that tire, and let it set in the hot sun all day. Be sure to put the tire under something that would provide protection if the tire desides to explode.
Then go back and measure it after you drop the pressure back down to the desired running pressure. If you have a rollout difference of less than 3/4 inch, or roughly 1/4 inch difference in diameter, dont even mess with it on a street vehicle.

The alternative would be to run the tire at about 10 lbs over the factory speck for a day, then let it back down to desired pressure, and compare. However, in the interest of safety, I DO NOT recommend doing this on a street vehicle. I wouldnt even swell a race tire that way on the track.
One other thing to consider, over inflating the tire in such a manner could easily void out your warrentee.

[pmeisel]

The links and formulas are correct if the tire is made exactly to the spec, which they often aren't. Tape measure, circumference divided by pi, is most accurate, and will change with tire pressure....

But if you ain't racin' for money, its all close enough, right?

The tires on our project jeep are shot so they get zero care, they are just there to roll it around the garage.... they are down some air and my sons wonder why the jeep is gettin g heavier and harder to push... they are still wondering why I had them air the tires up......

[bracketeer]

When buying slicks the manufacturer writes the circumference on the sidewall. They try to send you 2 tires as close as possible. Since a measuring tape between runs in a drag race is not practical. You buy an expensive pressure gage and set the pressure to within a 1/4 of a pound. I run my slicks at 7.5 psi

[segge]

Thanks for all the info, at first i was just looking for a rough number to put into a online calculator, but all this info will definitely come in handy