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rpm= MPH x total gear ratio x 336
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tire diameter

rpm= 75 x 3.73 x .72 (OD) x 336
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35

rpm= 1933.632

May be slightly higher as the tire won't actually measure a true 35 inches. Hope this helps.
 

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Discussion Starter · #4 ·
so its acualy gonna be great cause now with stock rims and tires i feel like im almost in the red zone! This will make a much quiet ride.
 

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I'm turning 2050rpm with 35's at 70. but I don't know what gears I have
 

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I'm running around 2100 rpm's at 75 with 3.73's
 

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Some one turned me onto this thread when I was deciding what gears to go with/with 37's :thumbsup:
you'll need to imput some info:
if not sure on some info, just measure your tire height, and rpm at a certain speed and you should be able to play with it and fig your gear ratio. info also depends man. or auto. The link will explain.. Good luck :party018:
Engine RPM Calculator
 

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and i think stock auto vs after market as well...
 

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To measure your true tire hieght go to your tire brand website. Not all 35s are 35s and using a tape measure doesnt do the diameter justice. I running firestone dest Mts. 315 70r 17s .. my tire size is 34.7 BFGs are 34.5 ect:confused013: ect
 

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actually the math on the 325 60 20 is basically 35.4''
 
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