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Speed per 1000 rpm



     To figure your speed in any gear (for any car) per 1000 rpm, use the 
     following formula:
     
             1                      1
     ----------------- * ----------------------- * 60 * 1000 = mph/1000 rpm 
     tire revs/mile      gear ratio * axle ratio
     
     Substituting some numbers from my Spider, in 2nd gear, gives
     (1/851)  *  (1/1.99)  *  (1/4.1) * 60 * 1000 = 8.64 mph / 1000 rpm,
     or to find speed at redline, divide by 1000 and multiply by redline:
     (8.64/1000) * 5700 = 49.25 mph in 2nd gear at redline.
     
     The only variable here is tire revs per mile. I used the number for 
     185-70x14 tires from Pirelli's tire info.
     
     Len

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