OT: tire stuff

mustang70

Founding Member

Nov 15, 2001

2,445

2

48

San Diego

May 7, 2004

#1

• May 7, 2004

• #1

I need to get new tires for my Mountaineer and I was thinking of going a little wider. The stock size is 235/75/15 and I would like to put a 255 on there. Isn't there something that if I go with a wider tire I should go with a shorter sidewall to maintain the same diameter? TIA.

 

G

gp001

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Jun 30, 2001

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So. Cal.

May 8, 2004

#2

• May 8, 2004

• #2

You would need an aspect ratio of 69 to maintain the same overall diameter

 

mustang70

Founding Member

Nov 15, 2001

2,445

2

48

San Diego

May 8, 2004

#3

• May 8, 2004

• #3

Hmmm....if I didn't know you any better, I would think you're offering me something.

I'm thinking I'll have to go with a 70 series and figure out what my difference on the speedo is going to be.

 

G

gp001

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Jun 30, 2001

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66

So. Cal.

May 8, 2004

#4

• May 8, 2004

• #4

Diameter of 235/75/15 is

{2 * [ (235x75) / 2540] } + 15 = 28.9 inches

Diameter of 255/70/15 is

{2 * [ (255x70) / 2540] } + 15 = 29.0 inches

Assuming your speedometer was correct with the 235 tire, your new MPH will be determined by multiplying your reading by 29.0 / 28.9 = 1.0034602076124567474048442906574

 

mustang70

Founding Member

Nov 15, 2001

2,445

2

48

San Diego

May 8, 2004

#5

• May 8, 2004

• #5

Just the smart guy aren't ya.








I have more to say, but this is a family website.

 

G

gp001

Founding Member

Jun 30, 2001

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66

So. Cal.

May 9, 2004

#6

• May 9, 2004

• #6

mustang70 said:

Just the smart guy aren't ya.








I have more to say, but this is a family website.

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