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3.55 gearing information - tires vs. rpm

tire size vs. rpm and speed

=($A17*I$4*PI()*60)/(I$3*12*5280)

a17 is engine rpm 
I4 is tire diameter  estimated 30.38 for the 31x10.5's...
Pi is pi... :) 3.1416
I3 is the gear ratio... in this case 3.55



Note:   Tire diameter is in INCHES.  Speed in Miles per hour.  Tach = rpm



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Gears: 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55 3.55
Tires: 28.88 29.38 29.88 30.38 30.88 31.38 31.88 32.38 32.88 33.38 33.88 34.38 34.88 35.38 35.88 36.38 36.88 37.38 37.88
tach mph mph mph mph mph mph mph mph mph mph mph mph mph mph mph mph mph mph mph
600 14.52 14.77 15.02 15.28 15.53 15.78 16.03 16.28 16.53 16.78 17.04 17.29 17.54 17.79 18.04 18.29 18.54 18.80 19.05
700 16.94 17.23 17.53 17.82 18.11 18.41 18.70 18.99 19.29 19.58 19.87 20.17 20.46 20.75 21.05 21.34 21.63 21.93 22.22
800 19.36 19.70 20.03 20.37 20.70 21.04 21.37 21.71 22.04 22.38 22.71 23.05 23.38 23.72 24.05 24.39 24.73 25.06 25.40
900 21.78 22.16 22.54 22.91 23.29 23.67 24.04 24.42 24.80 25.18 25.55 25.93 26.31 26.68 27.06 27.44 27.82 28.19 28.57
1000 24.20 24.62 25.04 25.46 25.88 26.30 26.72 27.14 27.55 27.97 28.39 28.81 29.23 29.65 30.07 30.49 30.91 31.33 31.74
1100 26.62 27.08 27.54 28.01 28.47 28.93 29.39 29.85 30.31 30.77 31.23 31.69 32.15 32.61 33.08 33.54 34.00 34.46 34.92
1200 29.04 29.55 30.05 30.55 31.05 31.56 32.06 32.56 33.07 33.57 34.07 34.57 35.08 35.58 36.08 36.58 37.09 37.59 38.09
1300 31.46 32.01 32.55 33.10 33.64 34.19 34.73 35.28 35.82 36.37 36.91 37.45 38.00 38.54 39.09 39.63 40.18 40.72 41.27
1400 33.88 34.47 35.06 35.64 36.23 36.82 37.40 37.99 38.58 39.16 39.75 40.34 40.92 41.51 42.10 42.68 43.27 43.86 44.44
1500 36.30 36.93 37.56 38.19 38.82 39.45 40.07 40.70 41.33