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2.72 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 3.31


Note: Tire diameter is in INCHES. Speed in Miles per hour. Tach = rpm
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Gears: 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72 2.72
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 18.95 19.28 19.61 19.94 20.26 20.59 20.92 21.25 21.58 21.91 22.23 22.56 22.89 23.22 23.55 23.87 24.20 24.53 24.86
700 22.11 22.49 22.88 23.26 23.64 24.03 24.41 24.79 25.17 25.56 25.94 26.32 26.70 27.09 27.47 27.85 28.24 28.62 29.00
800 25.27 25.71 26.14 26.58 27.02 27.46 27.89 28.33 28.77 29.21 29.64 30.08 30.52 30.96 31.39 31.83 32.27 32.71 33.14
900 28.43 28.92 29.41 29.91 30.40 30.89 31.38 31.87 32.37 32.86 33.35 33.84 34.33 34.83 35.32 35.81 36.30 36.80 37.29
1000 31.59 32.13 32.68 33.23 33.77 34.32 34.87 35.42 35.96 36.51 37.06 37.60 38.15 38.70 39.24 39.79 40.34 40.88 41.43
1100 34.75 35.35 35.95 36.55 37.15 37.75 38.36 38.96 39.56 40.16 40.76 41.36 41.96 42.57 43.17 43.77 44.37 44.97 45.57
1200 37.90 38.56 39.22 39.87 40.53 41.19 41.84 42.50 43.15 43.81 44.47 45.12 45.78 46.44 47.09 47.75 48.40 49.06 49.72
1300 41.06 41.77 42.49 43.20 43.91 44.62 45.33 46.04 46.75 47.46 48.17 48.88 49.59 50.31 51.02 51.73 52.44 53.15 53.86
1400 44.22 44.99 45.75 46.52 47.28 48.05 48.82 49.58 50.35 51.11 51.88 52.64 53.41 54.18 54.94 55.71 56.47 57.24 58.00
1500 47.38 48.20 49.02 49.84 50.66 51.48 52.30 53.12 53.94 54.76 55.58 56.40 57.22 58.05 58.87 59.69 60.51 61.33 62.15
1600 50.54 51.41 52.29 53.16 54.04 54.91 55.79 56.66 57.54 58.41 59.29 60.16 61.04 61.91 62.79 63.66 64.54 65.41 66.29
1700 53.70 54.63 55.56 56.49 57.42 58.35 59.28 60.21 61.14 62.07 63.00 63.93 64.85 65.78 66.71 67.64 68.57 69.50 70.43
1750 55.28 56.24 57.19 58.15 59.11 60.06 61.02 61.98 62.93 63.89 64.85 65.81 66.76 67.72 68.68 69.63 70.59 71.55 72.50
1850 58.44 59.45 60.46 61.47 62.48 63.50 64.51 65.52 66.53 67.54 68.55 69.57 70.58 71.59 72.60 73.61 74.62 75.64 76.65
1950 61.60 62.66 63.73 64.79 65.86 66.93 67.99 69.06 70.13 71.19 72.26 73.33 74.39 75.46 76.53 77.59 78.66 79.72 80.79
2050 64.75 65.88 67.00 68.12 69.24 70.36 71.48 72.60 73.72 74.84 75.97 77.09 78.21 79.33 80.45 81.57 82.69 83.81 84.93
2150 67.91 69.09 70.26 71.44 72.62 73.79 74.97 76.14 77.32 78.49 79.67 80.85 82.02 83.20 84.37 85.55 86.73 87.90 89.08
2250 71.07 72.30 73.53 74.76 75.99 77.22 78.45 79.68 80.92 82.15 83.38 84.61 85.84 87.07 88.30 89.53 90.76 91.99 93.22
2350 74.23 75.52 76.80 78.09 79.37 80.66 81.94 83.23 84.51 85.80 87.08 88.37 89.65 90.94 92.22 93.51 94.79 96.08 97.36
2450 77.39 78.73 80.07 81.41 82.75 84.09 85.43 86.77 88.11 89.45 90.79 92.13 93.47 94.81 96.15 97.49 98.83 100.17 101.51
2550 80.55 81.94 83.34 84.73 86.13 87.52 88.92 90.31 91.70 93.10 94.49 95.89 97.28 98.68 100.07 101.47 102.86 104.25 105.65
2650 83.71 85.16 86.61 88.05 89.50 90.95 92.40 93.85 95.30 96.75 98.20 99.65 101.10 102.55 104.00 105.44 106.89 108.34 109.79
2750 86.87 88.37 89.87 91.38 92.88 94.38 95.89 97.39 98.90 100.40 101.90 103.41 104.91 106.42 107.92 109.42 110.93 112.43 113.94
2850 90.02 91.58 93.14 94.70 96.26 97.82 99.38 100.93 102.49 104.05 105.61 107.17 108.73 110.29 111.84 113.40 114.96 116.52 118.08
2950 93.18 94.80 96.41 98.02 99.64 101.25 102.86 104.48 106.09 107.70 109.32 110.93 112.54 114.16 115.77 117.38 119.00 120.61 122.22
3050 96.34 98.01 99.68 101.35 103.01 104.68 106.35 108.02 109.69 111.35 113.02 114.69 116.36 118.03 119.69 121.36 123.03 124.70 126.37
3150 99.50 101.22 102.95 104.67 106.39 108.11 109.84 111.56 113.28 115.00 116.73 118.45 120.17 121.89 123.62 125.34 127.06 128.79 130.51
3250 102.66 104.44 106.21 107.99 109.77 111.55 113.32 115.10 116.88 118.66 120.43 122.21 123.99 125.76 127.54 129.32 131.10 132.87 134.65
3350 105.82 107.65 109.48 111.31 113.15 114.98 116.81 118.64 120.47 122.31 124.14 125.97 127.80 129.63 131.47 133.30 135.13 136.96 138.79
3450 108.98 110.86 112.75 114.64 116.52 118.41 120.30 122.18 124.07 125.96 127.84 129.73 131.62 133.50 135.39 137.28 139.16 141.05 142.94
3550 112.14 114.08 116.02 117.96 119.90 121.84 123.78 125.73 127.67 129.61 131.55 133.49 135.43 137.37 139.31 141.26 143.20 145.14 147.08
3650 115.29 117.29 119.29 121.28 123.28 125.27 127.27 129.27 131.26 133.26 135.25 137.25 139.25 141.24 143.24 145.24 147.23 149.23 151.22
3750 118.45 120.50 122.55 124.61 126.66 128.71 130.76 132.81 134.86 136.91 138.96 141.01 143.06 145.11 147.16 149.21 151.27 153.32 155.37
3850 121.61 123.72 125.82 127.93 130.03 132.14 134.24 136.35 138.46 140.56 142.67 144.77 146.88 148.98 151.09 153.19 155.30 157.40 159.51
3950 124.77 126.93 129.09 131.25 133.41 135.57 137.73 139.89 142.05 144.21 146.37 148.53 150.69 152.85 155.01 157.17 159.33 161.49 163.65
4050 127.93 130.14 132.36 134.57 136.79 139.00 141.22 143.43 145.65 147.86 150.08 152.29 154.51 156.72 158.94 161.15 163.37 165.58 167.80
4150 131.09 133.36 135.63 137.90 140.17 142.44 144.70 146.97 149.24 151.51 153.78 156.05 158.32 160.59 162.86 165.13 167.40 169.67 171.94
4250 134.25 136.57 138.89 141.22 143.54 145.87 148.19 150.52 152.84 155.16 157.49 159.81 162.14 164.46 166.79 169.11 171.43 173.76 176.08
4350 137.41 139.78 142.16 144.54 146.92 149.30 151.68 154.06 156.44 158.82 161.19 163.57 165.95 168.33 170.71 173.09 175.47 177.85 180.23
4450 140.56 143.00 145.43 147.86 150.30 152.73 155.17 157.60 160.03 162.47 164.90 167.33 169.77 172.20 174.63 177.07 179.50 181.94 184.37
4550 143.72                                    
4650 146.88                                    
4750 150.04                                    
4850 153.20                                    
4950 156.36                                    
5050 159.52                                    


Last Updated on 11/8/99
By John Meister
Email: john@johnmeister.com/jeep/sj