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Old 01-12-2011, 08:24 PM
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Whats my gear ratio if my rpms are exactly at 2000 at 70mph with 28.8 in tall tires(235/75/15)

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Old 01-12-2011, 08:56 PM
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Originally Posted by American Muscle
Whats my gear ratio if my rpms are exactly at 2000 at 70mph with 28.8 in tall tires(235/75/15)
http://www.ringpinion.com/Calc_RPM.aspx Plug it in and see.
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Old 01-12-2011, 09:20 PM
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It ask for a ratio and thats what i wanna know. I know tire height and the speed but do I just plug in some random gear ratio
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Old 01-12-2011, 09:46 PM
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Originally Posted by American Muscle
It ask for a ratio and thats what i wanna know. I know tire height and the speed but do I just plug in some random gear ratio
just start putting random ones until your numbers match
it will be like a gear ratio slot machine
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Old 01-12-2011, 10:11 PM
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I did. The closest numbers i come up with are with 3:42's. Is that right for a 97 ext cab 2wd. stock vortec 350. My dad n law truck.
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Old 01-12-2011, 10:47 PM
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The 3.42 is the most comon gear in those trucks. Look in the bottom of the glove box at the RPO sticker. You should find a GU6 code for the 3.42 gear.
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Old 01-12-2011, 11:10 PM
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I have these same gears in my 86 chevy and love it. im just looking for a good posi unit now.
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