1.37:1 rear gear ratio???

Old April 21st, 2019, 09:05 PM
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1.37:1 rear gear ratio???

I have to be doing my math wrong. I rotated the driveshaft while I had my wife count the tire rotations. At 4 driveshaft rotations, my wife tells me that the tire rotated almost three times exactly. Knowing this did not sound right, I turned the driveshaft 8 times and the wheel went just over 5 and 3/4 around. I have yet to get this project car on the road for the first time since I purchased this car.
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Old April 21st, 2019, 09:12 PM
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Not a 1.73 but maybe 2.73
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Old April 21st, 2019, 11:05 PM
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only works with a "posi" & transmission in nuetral

1 rotation of the tire & count the driveshaft's revolutions
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Old April 22nd, 2019, 01:43 AM
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If you are spinning only one tire you will only get half of the revolutions of the driveshaft due to the spider gears in the differential. That would net you a 2.73 gear ratio.
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Old April 22nd, 2019, 05:41 AM
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And it since it is half, it also means you have an open differential, no LSD.
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Old April 22nd, 2019, 01:24 PM
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Or a limited slip with severely worn clutches.
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Old April 23rd, 2019, 08:19 AM
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On a non-posi car, rotate the tire 2 turns while holding the other one from turning, & count the driveshaft revolutions to get the correct ratio.
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Old April 26th, 2019, 09:14 PM
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You guys are awesome. You're right of course, I'm half off. That puts me at 2.73 gears thanks!
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