tire heights?

[1987Rock]

Ok, I've been thinking about the difference in the overall tire diameter between a 315/35/17 and a 295/35/18.
It won't happen anytime soon, but for the money I would pay for a set of quality tires for 18s, I could buy another wheel/tire combo from 5.0resto etc and sell my old set for 500-600 and come out ahead.

I have 3.73s and do a good bit of highway driving, so I'm wondering how many more rev's I would have to turn with 17s. I would really love to get a set of 275/315 17s cuz those look SICK! on our cars I've got 18s with 245/275 and they just look skinny to me...

So does someone have/can someone take measurements of a 315/35/17 for the overall diameter and how wide they actually are? Thanks guys :SNSign:

 

[final5-0]

You may be able to go to a big discount tire chain like Discount Tire
or Tire Rack and find specs which will include various dimensions

You might do the same with the tire manufacturer

I've seen those specs somewhere but I forget where
but
Like X Files ... The Info Is Out There

Grady

 

[1987Rock]

I didn't think about that...I'll try that and do a better search. It was late last night and wasn't fully here while I was searching.

But if anyone wants to measure, that would be great. idk, but I think once they're mounted and on the car on the ground, it might make a small difference.

 

[j_lutter31]

The 315/35/17 will have a overall diameter of 26" and the 295/35/18 will have an overall diameter of 26.43"

So if you have a auto, your final tranny gear is 0.7

the 315's will have a rpm speed of 2362 and the 295's will have a rpm speed of 2324....very small difference, nothing to worry about

 

[SN95StangMan]

here you go

Tire size calculator

 

[j_lutter31]

that's a sweet little calculator, tells ya percent difference, actual speed....that page gets to go in the bookmarks....

 

[reddy351]

315 x .35 x 2 / 25.4 + 17 = overall tire diameter

The way this works is 315 (section width) x .35 (sidewall ratio) x 2 (1 "top" and 1 "bottom" sidewall) / 25.4 (to convert from mm to inches) + 17 (wheel diameter) = 25.68"

So you can apply this to any metric tire to get an idea of the overall height. (In case you don't have that handy dandy caculator...handy.)

 

[1987Rock]

Thanks guys! :SNSign:
I was having a hard time finding good calculators and that helped a bunch!

 

[j_lutter31]

oops i divided by 24.5 not 25.4 he is correct.....