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| Calculate RPM at given speed | |
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| Tweet Topic Started: Oct 30 2013, 01:04 PM (258 Views) | |
| SteveK | Oct 30 2013, 01:04 PM Post #1 |
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FYI... The following site will calculate your RPM's at a given speed if you know tire diameter, rear end ratio, and final ratio of transmission (1, OD, etc) http://www.csgnetwork.com/multirpmcalc.html With a 4.56 rear end, 26" tire size, and 1:1 trans final gear ratio, it says RPM should be 3241 RPM's at 55 MPH. You can plug in your own specifics to get what your Willys may be turning. Helpful if speedo seems off and and you have a tachometer, or you have changed tire size or ratios, or want to know impact first. It says my new 29" tires will reduce the RPM's to 2906 RPM's, and 3500 RPM's should yield 66 MPH (but not for long, I'm sure), and my speedo should be 11.5% slow from actual. I'm getting an adapter to correct that. Something that may be needed some day by someone. |
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SteveK 62 Dispatcher South Florida | |
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3:53 AM Jul 11