The Ford Barn - View Single Post - Volvo vs. Mitchell Over-Drive

DougVieyra · 08-10-2016, 11:31 AM

Within the spirit of 'controversy', when all the 'dust' has settled, it must be said that at the very bottom of the discussion there is the fact that using an over-drive, does for the most part, reduce engine RPMs for the same driving speed as a non-O.D. engine. As such, it would seem to me (a non-mechanic) that the reduced RPMs should help increase engine life, while still giving good motive power. That is to say, an O.D. gives the same speed as a non O.D., with significantly reduced engine RPM, hence (all things being equal) longer engine life.

Of course, all things are seldom equal, so in the long run, perhaps it really does not matter. But if nothing more than psychological, I REALLY enjoy having a Mitchel Over Drive in my '31 Dlx Coupe. And 65 years ago I enjoyed having a Columbia Rear End in my '28 Sedan.

08-10-2016, 11:31 AM	#39
DougVieyra Senior Member Join Date: Sep 2012 Location: Eureka, California Posts: 1,716	Re: Volvo vs. Mitchell Over-Drive - who has what? Within the spirit of 'controversy', when all the 'dust' has settled, it must be said that at the very bottom of the discussion there is the fact that using an over-drive, does for the most part, reduce engine RPMs for the same driving speed as a non-O.D. engine. As such, it would seem to me (a non-mechanic) that the reduced RPMs should help increase engine life, while still giving good motive power. That is to say, an O.D. gives the same speed as a non O.D., with significantly reduced engine RPM, hence (all things being equal) longer engine life. Of course, all things are seldom equal, so in the long run, perhaps it really does not matter. But if nothing more than psychological, I REALLY enjoy having a Mitchel Over Drive in my '31 Dlx Coupe. And 65 years ago I enjoyed having a Columbia Rear End in my '28 Sedan.