calc backup ::

Proformance Pros' Quick Change Gearset Ratio Calculator
Calculate your final ratio and max MPH by filling out the data inputs section.
Spreadsheet courtesy of Proformancepros.com

INPUT DATA IN YELLOW BOXES

Teeth

Ratio

1:1 Gearset with
4.08 Ratio

1.64:1 Gearset with
4.08 Ratio

2.421:1 Gearset with
4.08 Ratio

2.824:1 Gearset with
4.08 Ratio

MPH @
Given RPM

Driver

Driven

Input Tire Diameter -->

TC Drive Gear Ratio's to Select from:

Tire Diameter

2.048

8.35

13.70

20.23

23.59

22.06

Input Engine RPM-->

5000

1:1

2.000

8.16

13.38

19.76

23.04

22.58

Input TC Drive Gear Ratio -->

2.824:1

1.64:1

Engine RPM

5000

1.909

7.79

12.77

18.86

22.00

23.66

Input Ring and Pinion Ratio -->

4.08

2.421:1

1.864

7.60

12.47

18.41

21.47

24.23

2.824:1

TC Drive Gear Ratio

2.824:1

1.783

7.27

11.93

17.61

20.54

25.34

Ratios must be typed EXACTLY as shown

1.739

7.10

11.64

17.18

20.04

25.97

Ring & Pinion Ratio

4.08

1.667

6.80

11.15

16.46

19.20

27.10

1.625

6.63

10.87

16.05

18.72

27.79

1.594

6.50

10.66

15.74

18.36

28.34

1.560

6.36

10.44

15.41

17.97

28.95

1:1

1.538

6.28

10.29

15.20

17.73

29.36

=1:1N8

1.520

6.20

10.17

15.01

17.51

29.71

1.64:1

1.500

6.12

10.04

14.82

17.28

30.11

1.462

5.96

9.78

14.44

16.84

30.90

2.421:1

1.444

5.89

9.67

14.27

16.64

31.27

1.423

5.81

9.52

14.06

16.40

31.74

2.824:1

1.393

5.68

9.32

13.76

16.05

32.42

1.370

5.59

9.17

13.54

15.79

32.96

1.345

5.49

9.00

13.28

15.49

33.58

1.333

5.44

8.92

13.17

15.36

33.87

1.310

5.35

8.77

12.94

15.10

34.47

1.286

5.25

8.60

12.70

14.81

35.13

1.250

5.10

8.36

12.35

14.40

36.13

1.207

4.92

8.08

11.92

13.91

37.42

1.172

4.78

7.84

11.58

13.51

38.52

1.133

4.62

7.58

11.19

13.06

39.85

1.100

4.49

7.36

10.87

12.67

41.06

1.065

4.34

7.12

10.51

12.27

42.43

1.032

4.21

6.91

10.20

11.89

43.75

1.000

4.08

6.69

9.88

11.52

45.16

Overdriven Sets

0.969

3.95

6.48

9.57

11.16

46.62

0.939

3.83

6.29

9.28

10.82

48.08

0.909

3.71

6.08

8.98

10.47

49.68

0.882

3.60

5.90

8.72

10.17

51.18

0.853

3.48

5.71

8.43

9.83

52.95

Note Tooth Count when
placing your order.

0.829

3.38

5.54

8.18

9.55

54.51

0.800

3.26

5.35

7.90

9.22

56.45

0.778

3.17

5.20

7.68

8.96

58.07

0.750

3.06

5.02

7.41

8.64

60.22

0.730

2.98

4.88

7.21

8.41

61.89

0.703

2.87

4.70

6.94

8.10

64.27