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**Accelo** · 01-05-2023, 10:42 PM

Your motor rpm will drop by 18% with the gear change.

For arguments sake lets say you installed a typical OD transmission.
You typically get a lower first gear that helps get you moving.
You get double the 18% percentage drop in overdrive. (35%)
If you add the cost of ring and pinion and possible a carrier change.
Then add the labor and compare it to the benefits of an OD.
Your budget and mechanical skills will give you an answer.
Cheers.

01-05-2023, 10:42 PM	#6
Accelo Senior Member Join Date: Mar 2015 Location: washington Posts: 2,358	Re: 72 Saginaw 3 speed Speedo Drive gear? Your motor rpm will drop by 18% with the gear change. For arguments sake lets say you installed a typical OD transmission. You typically get a lower first gear that helps get you moving. You get double the 18% percentage drop in overdrive. (35%) If you add the cost of ring and pinion and possible a carrier change. Then add the labor and compare it to the benefits of an OD. Your budget and mechanical skills will give you an answer. Cheers.