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Old 07-12-2018, 08:32 AM   #28 (permalink)
JRMichler
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Join Date: Feb 2011
Location: Phillips, WI
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Nameless - '06 GMC Canyon
90 day: 37.45 mpg (US)

22 Maverick - '22 Ford Maverick XL
90 day: 42.77 mpg (US)
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Quote:
Originally Posted by hat_man View Post
I found this parts site and it showed a 3.27 in a 7.5" rear end.

Does anyone have any more information on these and can someone please help me with the math on rpm's with this ratio running in 5th gear (0.79 IIRC) at about 65 mph? Or if you can give me the math formula I can work it out.
Start with the revolutions per mile of your tires. Then multiply by the rear end ratio, and multiply again by the 5th gear ratio. The result is RPM at 60 MPH.

Example: Assume your tires are 700 revolutions per mile (that's a random number I pulled out of a dark place). Then you would get 700 X 3.27 X 0.79 = 1808 RPM at 60 MPH.

To get RPM at 65 MPH, scale by ratio of speeds: 1808 X 65 / 60 = 1959 RPM.
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06 Canyon: The vacuum gauge plus wheel covers helped increase summer 2015 mileage to 38.5 MPG, while summer 2016 mileage was 38.6 MPG without the wheel covers. Drove 33,021 miles 2016-2018 at 35.00 MPG.

22 Maverick: Summer 2022 burned 62.74 gallons in 3145.1 miles for 50.1 MPG. Winter 2023-2024 - 2416.7 miles, 58.66 gallons for 41 MPG.
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