Why do you want lower RPM?? Noise? Engine wear? Gas mileage?  I like running my 32 at 40-45 and it seems to like that speed. I have run at 60-65 for short periods (5-10 miles) and then neither I nor the car enjoy the ride. 

@steve-d 

want to run 50 to 55 without turning 3 grand. Some times 40 & 45 just not enough to keep up with the model as on some trips. They run an overdrive between the transmission & rear end. I might just drop one of them in my Chevy. Might be the easier way and maybe cheaper then a gear set.

@kevin-ray 50-55 MPH should put you at 24-2600 RPM .

@steve-d agree mine right at 2,700 at 55 just don’t like to run it that many rpm. Mine sounds goog between 2,000 & 2,500 rpm

just trying to keep it alive as long as I can

@kevin-ray I can understand as it took me a while to get used to the sound of my engine at higher RPM and it has been completely rebuilt. Keep in mind with higher gearing and lower RPM you will have less power.

@steve-d True. Thanks for all the advice from you and everyone else who have helped over the last few years. I hope to retain the knowledge from here and what I learn from my experience and be able to pass it along in future years. A vast of knowledge of these cars are leaving us daily. Safe driving to all.

@kevin-ray 

"A vast of knowledge of these cars are leaving us daily. Safe driving to all"

True.

Someone once said:

When an old man/woman dies... a library burns to the ground.

    For different engine RPMs at different ratios with different tire size,  look at web page:  http://home.znet.com/c1937/RPM.htm .       

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Posted by: @steve-d

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