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4.88 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: |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
4.88 |
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 |
10.56 |
10.75 |
10.93 |
11.11 |
11.30 |
11.48 |
11.66 |
11.84 |
12.03 |
12.21 |
12.39 |
12.58 |
12.76 |
12.94 |
13.12 |
13.31 |
13.49 |
13.67 |
13.86 |
700 |
12.32 |
12.54 |
12.75 |
12.96 |
13.18 |
13.39 |
13.60 |
13.82 |
14.03 |
14.24 |
14.46 |
14.67 |
14.88 |
15.10 |
15.31 |
15.52 |
15.74 |
15.95 |
16.16 |
800 |
14.08 |
14.33 |
14.57 |
14.82 |
15.06 |
15.30 |
15.55 |
15.79 |
16.04 |
16.28 |
16.52 |
16.77 |
17.01 |
17.25 |
17.50 |
17.74 |
17.99 |
18.23 |
18.47 |
900 |
15.85 |
16.12 |
16.39 |
16.67 |
16.94 |
17.22 |
17.49 |
17.77 |
18.04 |
18.31 |
18.59 |
18.86 |
19.14 |
19.41 |
19.69 |
19.96 |
20.23 |
20.51 |
20.78 |
1000 |
17.61 |
17.91 |
18.22 |
18.52 |
18.83 |
19.13 |
19.43 |
19.74 |
20.04 |
20.35 |
20.65 |
20.96 |
21.26 |
21.57 |
21.87 |
22.18 |
22.48 |
22.79 |
23.09 |
1100 |
19.37 |
19.70 |
20.04 |
20.37 |
20.71 |
21.04 |
21.38 |
21.71 |
22.05 |
22.38 |
22.72 |
23.05 |
23.39 |
23.73 |
24.06 |
24.40 |
24.73 |
25.07 |
25.40 |
1200 |
21.13 |
21.49 |
21.86 |
22.22 |
22.59 |
22.96 |
23.32 |
23.69 |
24.05 |
24.42 |
24.79 |
25.15 |
25.52 |
25.88 |
26.25 |
26.61 |
26.98 |
27.35 |
27.71 |
1300 |
22.89 |
23.28 |
23.68 |
24.08 |
24.47 |
24.87 |
25.27 |
25.66 |
26.06 |
26.45 |
26.85 |
27.25 |
27.64 |
28.04 |
28.44 |
28.83 |
29.23 |
29.62 |
30.02 |
1400 |
24.65 |
25.08 |
25.50 |
25.93 |
26.36 |
26.78 |
27.21 |
27.64 |
28.06 |
28.49 |
28.92 |
29.34 |
29.77 |
30.20 |
30.62 |
31.05 |
31.48 |
31.90 |
32.33 |
1500 |
26.41 |
26.87 |
27.32 |
27.78 |
28.24 |
28.70 |
29.15 |
29.61 |
30.07 |
30.52 |
30.98 |
31.44 |
31.90 |
32.35 |
32.81 |
33.27 |
33.72 |
34.18 |
34.64 |
1600 |
28.17 |
28.66 |
29.15 |
29.63 |
30.12 |
30.61 |
31.10 |
31.58 |
32.07 |
32.56 |
33.05 |
33.53 |
34.02 |
34.51 |
35.00 |
35.49 |
35.97 |
36.46 |
36.95 |
1700 |
29.93 |
30.45 |
30.97 |
31.48 |
32.00 |
32.52 |
33.04 |
33.56 |
34.08 |
34.59 |
35.11 |
35.63 |
36.15 |
36.67 |
37.18 |
37.70 |
38.22 |
38.74 |
39.26 |
1750 |
30.81 |
31.34 |
31.88 |
32.41 |
32.94 |
33.48 |
34.01 |
34.54 |
35.08 |
35.61 |
36.14 |
36.68 |
37.21 |
37.75 |
38.28 |
38.81 |
39.35 |
39.88 |
40.41 |
1850 |
32.57 |
33.14 |
33.70 |
34.26 |
34.83 |
35.39 |
35.95 |
36.52 |
37.08 |
37.65 |
38.21 |
38.77 |
39.34 |
39.90 |
40.47 |
41.03 |
41.59 |
42.16 |
42.72 |
1950 |
34.33 |
34.93 |
35.52 |
36.12 |
36.71 |
37.30 |
37.90 |
38.49 |
39.09 |
39.68 |
40.28 |
40.87 |
41.46 |
42.06 |
42.65 |
43.25 |
43.84 |
44.44 |
45.03 |
2050 |
36.09 |
36.72 |
37.34 |
37.97 |
38.59 |
39.22 |
39.84 |
40.47 |
41.09 |
41.72 |
42.34 |
42.97 |
43.59 |
44.22 |
44.84 |
45.47 |
46.09 |
46.72 |
47.34 |
2150 |
37.85 |
38.51 |
39.16 |
39.82 |
40.47 |
41.13 |
41.79 |
42.44 |
43.10 |
43.75 |
44.41 |
45.06 |
45.72 |
46.37 |
47.03 |
47.68 |
48.34 |
48.99 |
49.65 |
2250 |
39.61 |
40.30 |
40.99 |
41.67 |
42.36 |
43.04 |
43.73 |
44.41 |
45.10 |
45.79 |
46.47 |
47.16 |
47.84 |
48.53 |
49.22 |
49.90 |
50.59 |
51.27 |
51.96 |
2350 |
41.37 |
42.09 |
42.81 |
43.52 |
44.24 |
44.96 |
45.67 |
46.39 |
47.10 |
47.82 |
48.54 |
49.25 |
49.97 |
50.69 |
51.40 |
52.12 |
52.84 |
53.55 |
54.27 |
2450 |
43.13 |
43.88 |
44.63 |
45.38 |
46.12 |
46.87 |
47.62 |
48.36 |
49.11 |
49.86 |
50.60 |
51.35 |
52.10 |
52.84 |
53.59 |
54.34 |
55.08 |
55.83 |
56.58 |
2550 |
44.90 |
45.67 |
46.45 |
47.23 |
48.00 |
48.78 |
49.56 |
50.34 |
51.11 |
51.89 |
52.67 |
53.45 |
54.22 |
55.00 |
55.78 |
56.55 |
57.33 |
58.11 |
58.89 |
2650 |
46.66 |
47.46 |
48.27 |
49.08 |
49.89 |
50.69 |
51.50 |
52.31 |
53.12 |
53.93 |
54.73 |
55.54 |
56.35 |
57.16 |
57.96 |
58.77 |
59.58 |
60.39 |
61.20 |
2750 |
48.42 |
49.26 |
50.09 |
50.93 |
51.77 |
52.61 |
53.45 |
54.28 |
55.12 |
55.96 |
56.80 |
57.64 |
58.48 |
59.31 |
60.15 |
60.99 |
61.83 |
62.67 |
63.51 |
2850 |
50.18 |
51.05 |
51.91 |
52.78 |
53.65 |
54.52 |
55.39 |
56.26 |
57.13 |
58.00 |
58.86 |
59.73 |
60.60 |
61.47 |
62.34 |
63.21 |
64.08 |
64.95 |
65.81 |
2950 |
51.94 |
52.84 |
53.74 |
54.64 |
55.53 |
56.43 |
57.33 |
58.23 |
59.13 |
60.03 |
60.93 |
61.83 |
62.73 |
63.63 |
64.53 |
65.43 |
66.33 |
67.22 |
68.12 |
3050 |
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 |
3150 |
55.46 |
56.42 |
57.38 |
58.34 |
59.30 |
60.26 |
61.22 |
62.18 |
63.14 |
64.10 |
65.06 |
66.02 |
66.98 |
67.94 |
68.90 |
69.86 |
70.82 |
71.78 |
72.74 |
3250 |
57.22 |
58.21 |
59.20 |
60.19 |
61.18 |
62.17 |
63.16 |
64.15 |
65.15 |
66.14 |
67.13 |
68.12 |
69.11 |
70.10 |
71.09 |
72.08 |
73.07 |
74.06 |
75.05 |
3350 |
58.98 |
60.00 |
61.02 |
62.04 |
63.06 |
64.09 |
65.11 |
66.13 |
67.15 |
68.17 |
69.19 |
70.21 |
71.23 |
72.26 |
73.28 |
74.30 |
75.32 |
76.34 |
77.36 |
3450 |
60.74 |
61.79 |
62.84 |
63.90 |
64.95 |
66.00 |
67.05 |
68.10 |
69.15 |
70.21 |
71.26 |
72.31 |
73.36 |
74.41 |
75.46 |
76.52 |
77.57 |
78.62 |
79.67 |
3550 |
62.50 |
63.58 |
64.67 |
65.75 |
66.83 |
67.91 |
68.99 |
70.08 |
71.16 |
72.24 |
73.32 |
74.40 |
75.49 |
76.57 |
77.65 |
78.73 |
79.82 |
80.90 |
81.98 |
3650 |
64.26 |
65.37 |
66.49 |
67.60 |
68.71 |
69.83 |
70.94 |
72.05 |
73.16 |
74.28 |
75.39 |
76.50 |
77.61 |
78.73 |
79.84 |
80.95 |
82.06 |
83.18 |
84.29 |
3750 |
66.02 |
67.17 |
68.31 |
69.45 |
70.60 |
71.74 |
72.88 |
74.02 |
75.17 |
76.31 |
77.45 |
78.60 |
79.74 |
80.88 |
82.03 |
83.17 |
84.31 |
85.45 |
86.60 |
3850 |
67.78 |
68.96 |
70.13 |
71.30 |
72.48 |
73.65 |
74.82 |
76.00 |
77.17 |
78.35 |
79.52 |
80.69 |
81.87 |
83.04 |
84.21 |
85.39 |
86.56 |
87.73 |
88.91 |
3950 |
69.54 |
70.75 |
71.95 |
73.16 |
74.36 |
75.56 |
76.77 |
77.97 |
79.18 |
80.38 |
81.58 |
82.79 |
83.99 |
85.20 |
86.40 |
87.60 |
88.81 |
90.01 |
91.22 |
4050 |
71.30 |
72.54 |
73.77 |
75.01 |
76.24 |
77.48 |
78.71 |
79.95 |
81.18 |
82.42 |
83.65 |
84.88 |
86.12 |
87.35 |
88.59 |
89.82 |
91.06 |
92.29 |
93.53 |
4150 |
73.07 |
74.33 |
75.60 |
76.86 |
78.13 |
79.39 |
80.66 |
81.92 |
83.19 |
84.45 |
85.72 |
86.98 |
88.25 |
89.51 |
90.78 |
92.04 |
93.31 |
94.57 |
95.84 |
4250 |
74.83 |
76.12 |
77.42 |
78.71 |
80.01 |
81.30 |
82.60 |
83.89 |
85.19 |
86.49 |
87.78 |
89.08 |
90.37 |
91.67 |
92.96 |
94.26 |
95.55 |
96.85 |
98.14 |
4350 |
76.59 |
77.91 |
79.24 |
80.56 |
81.89 |
83.22 |
84.54 |
85.87 |
87.19 |
88.52 |
89.85 |
91.17 |
92.50 |
93.82 |
95.15 |
96.48 |
97.80 |
99.13 |
100.45 |
4450 |
78.35 |
79.70 |
81.06 |
82.42 |
83.77 |
85.13 |
86.49 |
87.84 |
89.20 |
90.56 |
91.91 |
93.27 |
94.62 |
95.98 |
97.34 |
98.69 |
100.05 |
101.41 |
102.76 |
Last Updated on 3/17/01
By John Meister
Email: john@johnmeister.com/jeep/sj