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414TATA

R P M Question

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Re: 248 C.I. Straight eight. My question. How many R M P is this beast turning at 55-60 Miles per hours?

I know this has been discussed many times but when I do a search using RPM nothing comes up for me.

If you can stand the repetition I hope you will help me out.:)

Thanks

Wayne

1941 Super 51

post-78086-143141749194_thumb.jpg

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There are formulas out there that you can find, and web pages with handy calculators. If you know your wheel diameter, diff ratio and the speed you're wanting to know about, it should be able to tell you.

Cheers

Grant

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For 1931 the "Specifications and Adjustments" Manual has a very good graph for road speed in relation to engine RPM showing exact figures which differ for each model, not just engine size-the more "sporty" open cars seeming to rev higher than the big saloons.

It shows the largest car/engine (Series 90-344.8 CI) doing 3000RPM at 65MPH and the smaller (Series 50-220.7CI) doing 3500+at 65MPH

I assume the manual for 1941 should have the same info?

cheers

Jules

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The '38 manual has such a graph. It's at home now, so I will just rely on memory. A '38 Special with 248 engine and 4.44 rear turns about 3200 rpm at 60 and the Century with 320 engine and 3.9 rear turns about 2800 rpm at 60. Again, just going with my memory (usually faulty).

Jeff

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Thanks Gentlemen

I was thinking in the range of 3,000 RPM at 55 - 60 mph. Seems that number came to mind from a prior post.:)

Wayne B.

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I just looked in my '41 manual, and with the 4.4 axle, it shows dead on 3200 RPM at 60 MPH, if you have the optional 4.1 ratio, it shows just a tick under 3000.

Keith

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