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Conversion Calculators

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The calculators below provide a pretty close estimate -- but it is not an exact science. You may experience slightly different results on the track due to track conditions, gearing and tire size, clutch or convertor, and other differences with the car

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?1/8-MILE TO 1/4-MILE CONVERSION TABLE

1/8-mile ET

1/4-mile ET

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1/8-mile ET

1/4-mile ET

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1/8-mile ET

1/4-mile ET

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1/8-mile ET

1/4-mile ET
5 7.80 ? 6.8 10.61 ? 8.55 13.34 ? 10.3 16.07
5.05 7.88 ? 6.85 10.69 ? 8.6 13.42 ? 10.35 16.15
5.1 7.96 ? 6.9 10.76 ? 8.65 13.49 ? 10.4 16.22
5.15 8.03 ? 6.95 10.84 ? 8.7 13.57 ? 10.45 16.30
5.2 8.11 ? 7 10.92 ? 8.75 13.65 ? 10.5 16.38
5.25 8.19 ? 7.05 11.00 ? 8.8 13.73 ? 10.55 16.46
5.3 8.27 ? 7.1 11.08 ? 8.85 13.81 ? 10.6 16.54
5.35 8.35 ? 7.15 11.15 ? 8.9 13.88 ? 10.65 16.61
5.4 8.42 ? 7.2 11.23 ? 8.95 13.96 ? 10.7 16.69
5.45 8.50 ? 7.25 11.31 ? 9 14.04 ? 10.75 16.77
5.5 8.58 ? 7.3 11.39 ? 9.05 14.12 ? 10.8 16.85
5.55 8.66 ? 7.35 11.47 ? 9.1 14.20 ? 10.85 16.93
5.6 8.74 ? 7.4 11.54 ? 9.15 14.27 ? 10.9 17.00
5.65 8.81 ? 7.45 11.62 ? 9.2 14.35 ? 10.95 17.08
5.7 8.89 ? 7.5 11.70 ? 9.25 14.43 ? 11 17.16
5.75 8.97 ? 7.55 11.78 ? 9.3 14.51 ? 11.05 17.24
5.8 9.05 ? 7.6 11.86 ? 9.35 14.59 ? 11.1 17.32
5.85 9.13 ? 7.65 11.93 ? 9.4 14.66 ? 11.15 17.39
5.9 9.20 ? 7.7 12.01 ? 9.45 14.74 ? 11.2 17.47
5.95 9.28 ? 7.75 12.09 ? 9.5 14.82 ? 11.25 17.55
6 9.36 ? 7.8 12.17 ? 9.55 14.90 ? 11.3 17.63
6.05 9.44 ? 7.85 12.25 ? 9.6 14.98 ? 11.35 17.71
6.1 9.52 ? 7.9 12.32 ? 9.65 15.05 ? 11.4 17.78
6.15 9.59 ? 7.95 12.40 ? 9.7 15.13 ? 11.45 17.86
6.2 9.67 ? 8 12.48 ? 9.75 15.21 ? 11.5 17.94
6.25 9.75 ? 8.05 12.56 ? 9.8 15.29 ? 11.55 18.02
6.3 9.83 ? 8.1 12.64 ? 9.85 15.37 ? 11.6 18.10
6.35 9.91 ? 8.15 12.71 ? 9.9 15.44 ? 11.65 18.17
6.4 9.98 ? 8.2 12.79 ? 9.95 15.52 ? 11.7 18.25
6.45 10.06 ? 8.25 12.87 ? 10 15.60 ? 11.75 18.33
6.5 10.14 ? 8.3 12.95 ? 10.05 15.68 ? 11.8 18.41
6.55 10.22 ? 8.35 13.03 ? 10.1 15.76 ? 11.85 18.49
6.6 10.30 ? 8.4 13.10 ? 10.15 15.83 ? 11.9 18.56
6.65 10.37 ? 8.45 13.18 ? 10.2 15.91 ? 11.95 18.64
6.7 10.45 ? 8.5 13.26 ? 10.25 15.99 ? 12 18.72
6.75 10.53 ? ? ? ? ? ? ? ? ?


Calculate Your HP from Your Speed

Vehicle weight in pounds (including driver)
 lbs

Trap speed at end of 1/4 mi in m.p.h.
 MPH


Uncorrected HP is :

This is the estimate Horse Power at the flywheel

???????????????? / Trap Speed (mph) \ 3
? Horse Power = | ------------------|? x Vehicle Weight
???????????????? \??????? 234?????? /

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Calculate Your HP from Your ET

Vehicle weight in pounds (including driver)
 lbs

ET in seconds
 sec


Uncorrected HP is :

This is the estimate Horse Power at the flywheel

???????? ??????? /???? 5.825??? \ 3
? Horse Power = | -------------- |? x Vehicle Weight
???????????????? \ Elapsed Time /


Calculate Your MPH for Your RPM
Tire diameter
 		Gear Ratio

This calculation is for a final drive ratio of 1:1
1000 rpm mph 4500 rpm mph
1500 rpm mph 5000 rpm mph
2000 rpm mph 5500 rpm mph
2500 rpm mph 6000 rpm mph
3000 rpm mph 6500 rpm mph
3500 rpm mph 7000 rpm mph
4000 rpm mph 7500 rpm mph

Calculate Your Rear End Gear Ratio

Enter the tire diameter in inches, the rpm's of the engine at entered speed as indicated by your speedometer in mph. This calculator is for a 1:1 final drive ratio.
Tire Diameter (in)
 		RPM
 		Speed at RPM (mph)


Final Rear Gear Ratio





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