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These calculators are designed to give the approximate engine RPM (revolutions per minute) based on the ring gear and pinion gear ratio, the height of the tires (diameter from ground to top of the tire while mounted on the vehicle) and the transmission final gear ratio.
This calculator does not take into consideration any drive train loss, road and weather conditions or driver skills. The calculated results are displayed; the higher the engine RPM, the greater the potential speed at the cost of fuel, heat, friction and engine longevity. The results are only an Estimate - Your Mileage May Vary (litterally).
"Ideal" 65MPH Cruising Speed RPMs Based on Tire Size (estimated)
27"
|
28"
|
29"
|
30"
|
31"
|
32"
|
33"
|
34"
|
35"
|
36"
|
37"
|
38"
|
40"
|
42"
|
44"
|
1,752
|
1,690
|
1,631
|
1,577
|
1,526
|
1,478
|
1,434
|
1,391
|
1,352
|
1,314
|
1,279
|
1,245
|
1,183
|
1,126
|
1,075
|
1,869
|
1,802
|
1,740
|
1,682
|
1,627
|
1,577
|
1,529
|
1,484
|
1,441
|
1,401
|
1,364
|
1,328
|
1,261
|
1,201
|
1,147
|
2,012
|
1,942
|
1,874
|
1,811
|
1,753
|
1,698
|
1,646
|
1,599
|
1,552
|
1,509
|
1,468
|
1,429
|
1,358
|
1,294
|
1,235
|
2,108
|
2,033
|
1,963
|
1,897
|
1,836
|
1,779
|
1,725
|
1,674
|
1,626
|
1,581
|
1,538
|
1,498
|
1,423
|
1,355
|
1,294
|
2,197
|
2,119
|
2,046
|
1,977
|
1,914
|
1,854
|
1,798
|
1,745
|
1,695
|
1,648
|
1,603
|
1,561
|
1,483
|
1,412
|
1,348
|
2,266
|
2,185
|
2,110
|
2,039
|
1,973
|
1,912
|
1,854
|
1,799
|
1,748
|
1,699
|
1,653
|
1,610
|
1,529
|
1,456
|
1,390
|
2,341
|
2,257
|
2,179
|
2,107
|
2,039
|
1,975
|
1,915
|
1,859
|
1,806
|
1,756
|
1,708
|
1,663
|
1,580
|
1,505
|
1,436
|
2,423
|
2,336
|
2,256
|
2,181
|
2,110
|
2,044
|
1,982
|
1,924
|
1,869
|
1,817
|
1,768
|
1,772
|
1,635
|
1,558
|
1,487
|
2,553
|
2,462
|
2,377
|
2,298
|
2,224
|
2,154
|
2,089
|
2,027
|
1,969
|
1,915
|
1,863
|
1,814
|
1,723
|
1,641
|
1,567
|
2,669
|
2,574
|
2,485
|
2,402
|
2,325
|
2,252
|
2,184
|
2,120
|
2,059
|
2,002
|
1,948
|
1,897
|
1,802
|
1,716
|
1,638
|
2,806
|
2,706
|
2,613
|
2,526
|
2,444
|
2,368
|
2,296
|
2,228
|
2,165
|
2,105
|
2,048
|
1,994
|
1,894
|
1,804
|
1,722
|
2,923
|
2,818
|
2,721
|
2,630
|
2,545
|
2,466
|
2,391
|
2,321
|
2,255
|
2,195
|
2,133
|
2,077
|
1,973
|
1,879
|
1,793
|
3,121
|
3,010
|
2,906
|
2,809
|
2,718
|
2,633
|
2,554
|
2,478
|
2,408
|
2,341
|
2,278
|
2,218
|
2,107
|
2,006
|
1,915
|
3,340
|
3,221
|
3,110
|
3,006
|
2,909
|
2,818
|
2,733
|
2,652
|
2,577
|
2,505
|
2,437
|
2,373
|
2,255
|
2,147
|
2,050
|
3,621
|
3,491
|
3,371
|
3,259
|
3,154
|
3,055
|
2,962
|
2,875
|
2,793
|
2,716
|
2,642
|
2,573
|
2,444
|
2,328
|
2,222
|
3,682
|
3,551
|
3,428
|
3,314
|
3,207
|
3,107
|
3,013
|
2,924
|
2,841
|
2,762
|
2,687
|
2,616
|
2,486
|
2,367
|
2,260
|
3,908
|
3,769
|
3,639
|
3,517
|
3,404
|
3,298
|
3,198
|
3,104
|
3,015
|
2,931
|
2,852
|
2,777
|
2,638
|
2,512
|
2,398
|
4,223
|
4,072
|
3,932
|
3,801
|
3,678
|
3,653
|
3,455
|
3,354
|
3,258
|
3,167
|
3,082
|
3,001
|
2,851
|
2,715
|
2,593
|
4,907
|
4,732
|
4,569
|
4,417
|
4,274
|
4,141
|
4,015
|
3,897
|
3,786
|
3,681
|
3,581
|
3,487
|
3,313
|
3,155
|
3,011
|
Acceptable RPM range is
shaded on the above chart. The optimum RPM
range is shaded in green
The results from this webpage are not guaranteed to be accurate - please check with your local professional for exact figures
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