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Re: Speed Application
> MPH = (RPM * TireDiameter)/(Gear Ratio * 1000)
> TireDiameter = ((Section Width * Aspect Ratio)/25.4) * 2 + RIM
> Gear Ratio
> 1 3.78
> 2 2.12
> 3 1.46
> 4 1.03
> 5 .84
> R 3.80
> F 3.39
>
> so sample
> 205/50 R15 at 3000RPM in 3rd gear on a Jetta GLX
>
> TD = (205 * .50)/25.4 * 2 + 15
> TD = 23.08"
> MPH = (3000 * 23.08)/1.46 * 1000
> MPH = 47.4
> Real World showed pretty close results.
>
So, let me get this straight....
Let's sample Top speed.
205/50 R15 at 6500RPM in 5th gear on a Jetta GLX
TD = 23.08" (Stays the same)
MPH = (6500 * 23.08)/(0.84 * 1000)
MPH = 178.6 WOW!!!!
Maybe some drag calculations should be thrown in there....
I think most simple calculations get tossed out once you
include drag forces, tire traction, etc... I think you're
better off just driving the car and timing/measuring it
yourself.
--
Benjamin M. Piecuch
Hamilton Standard
Space Systems International