Calculating rear ratio question

Clutch, transmission, rear axle

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jdconnel
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Calculating rear ratio question

Post by jdconnel »

So... I thought I knew what I was doing.
I marked the tire, and the axel. Jack the back up and spun the drive shaft.
I get 1.75 revolutions on the drive shaft for 1 on the passenger tire.
There's no way that's my ratio. Is it x2 for 3.50, which would make sense, or am I not remembering how to do this right?
-=Life's Too Short to Drink Cheap Beer=-
1973 F-100 Custom Sport (Previously had 1967 & 1970 F-250)
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Fordkid68
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Re: Calculating rear ratio question

Post by Fordkid68 »

Here is a video on how to measure the ratio. It is really helpful.

https://www.youtube.com/watch?v=RNgjS5mHI0E
Adam

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1968 F100 lwb 2wd soon to have a 351w, 5-speed
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jdconnel
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Re: Calculating rear ratio question

Post by jdconnel »

Thanks!
Seems it IS x2. I got a solid 1.75, so it been swapped for a 3.50.
Math checks out for the speedometer drift as well.
-=Life's Too Short to Drink Cheap Beer=-
1973 F-100 Custom Sport (Previously had 1967 & 1970 F-250)
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