Kevin,

TexasJim50 is correct!

A little searching and I found this thread about determining rear axle gear ratios. Taken from this thread, the correct math would be taking your 17.7 rotations times 2 = 35.40, divided by 10 = 3.54.

I would hazard that there is just a wee bit of fudge factor in your rotation number and that you actually have a 3:55 - 1 ratio. That was stock in the axles installed in passenger cars behind auto transmissions as noted in my earlier post above.

Am sure more folks will chime in about the automatic transmission mount requirements soon. wink

Dan

Last edited by Gdads51; 08/26/2023 10:25 PM.
~ Dan
1951 Chevy 3 window 3100
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