Aspect Ratio for Front

SeventyMach1

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I'll be bumping up to a 265 for the front, as I have a little rim showing. It makes me nervous. Let's just say if I curbed it, I would be pissed.


I run a 315/35/17 out back. What aspect ratio for a 265 tire would have the equivalent sidewall to a 315 tire? Would 265/40/17 match up perfect? 265/45/17? Or what?

Sidewall is nice ..... because of the comfort of the ride. But I'm tired of the look. The one's I've got have WAY too much sidewall. Plus, when I lower the car, it might not even clear good. So I want to widen the tire, but lower the aspect ratio. Any advice?

 

OrangeMustangGt

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i would think that the sidewall hight you would want would be the same number as the rear, i mean with shouldent affect sidewall height. I am running 295/35/18s rear and 265/35/18s front, and the sidewalls are exactly the same height

 

Mustangless

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http://www.miata.net/garage/tirecalc.html

This should help you. A 265/40/17 would have a 4.2in sidewall
A 265/45/17 would have a 4.7in sidewall
A 275/40/17 would have a 4.3in sidewall

315/35/17 has a 4.3in sidewall too.






After looking at this, I should have ordered 255/40s not 255/45s. I guess I will go up to the 275/40 next time

 

HISSIN50

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GreenMustangGt said:

i would think that the sidewall hight you would want would be the same number as the rear, i mean with shouldent affect sidewall height. I am running 295/35/18s rear and 265/35/18s front, and the sidewalls are exactly the same height

Click to expand...

the aspect ratio is the percentage of the width of the tire. So with 295/35's, the height is 35% of the width (0.35*295mm). And the fronts are 265mm * .35.

But the numbers can be off since dimensions from one tire manufacturer to another vary. And mounted heights can vary as well (wheel width etc as a factor).

I have found that crunching the numbers gets you close but you almost have to mount/mock up the tires on the rims to make sure it will have the right height and look.

Good luck.

 

SeventyMach1

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Yeah, I knew that the aspect ratio was a percentage .... that's why I asked the question. Otherwise I would have just got the same. Maybe you lucked up Kyle ..... do you run the same brand tires front & back? Thanks guys.

 

SeventyMach1

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Thanks for that link Mustangless. What do you run out back? I'm thinking I'll need the 265/40's up front, at 0.1" smaller than the rears. Or maybe the 265/45's at 0.4" taller than the rears. But I'm leaning with the 40's.

 

HISSIN50

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SeventyMach1 said:

Yeah, I knew that the aspect ratio was a percentage .... that's why I asked the question. Otherwise I would have just got the same. Maybe you lucked up Kyle ..... do you run the same brand tires front & back? Thanks guys.

Click to expand...

From the choices you listed in the opening post, I knew you knew that Justin.

I was just trying to clarify and explain how Kyle might have ended up with the same absolute heights on his tires. Then again, it seems to me the difference in his sidewall heights is only around 10 mm, which aint much to the bare eye.

 

SeventyMach1

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Looking back ay my post, I guess I did sound kind of rude. Sorry about that. Nah, I wasn't shooting that post at you JT. (or anyone really).

 

HISSIN50

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OrangeMustangGt

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yeah good point, im sure there is a diffrence, i just dont notice it