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Discussion Starter #1
Please submit photos of your GTO's using 60 series tires on back and 70s series tires on front. Please indicate the size tires/wheels you are running. Trying to switch to wider 60s tire that doesn't affect the original stance of the Classic Look! Thanks!!
 

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ottfive,
60 and 70 are actually the aspect ratio and determine the sidewall height, Here is a breakdown of a 245/60/14 tire;

245 x .03937 (metric conversion)= 9.645" tire width at the widest point,
9.645 x .60 (aspect ratio)= 5.78 sidewall height
5.78 x 2 + 14" wheel = 25.56" tire height,
 

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Discussion Starter #5
So I'm currently at a 205x75x14 tires on back giving me 29 .3 tire height? so this would change my effective rearend ratio of 3.55 by going to a smaller tire height? Thanks for the info.
 

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"Shorter" (smaller diameter) tires have the effect of slightly lowering (numerically increasing) the gear ratio, "taller" (larger diameter) tires have the opposite effect.

You can calculate the differences if you know "all the numbers": current gear ratio, current tire diameter, "new" tire diameter.

Bear
 

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The main thing here is to get the offset of the rims correct, so that whatever tire you use, it doesn't rub into the fender well. Nothing more 'hack' than seeing wheel wells cut or hammered out to clear ill-fitting wheels.
 

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Discussion Starter #8
I agree no cutting will be done, I'm looking at 225x70x14 front and 225 or 245 x 60 x14 on rear my wheels are cragers 14x7. Thanks!
 
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