Well, I ran my truck down the 1/8th mile track over the weekend, and with a bunch of the online conversion calculators it told me that my truck is about 487hp.(adsbygoogle = window.adsbygoogle || []).push({});

So I plugged in the old kinematics formulas, and i got quite a discrepancy between them.. Did I do the math right?

Time = 10.055s

Speed (from trap speed) = 75 mph = 33.5 m/s

Distance =1/8th mile, 201.2m

Mass = 7370 lbs = 3350kg

Ke = 1/2 mv^{2}= 1883 KJ

P = 1883/10.055 = 187 KW

P = 187/.745 = 251 hp...

Yes, that's perfect world, no friction, wind resistance, and doesn't include Ke left in the drivetrain

that's pretty much half of what the online calculators come up with

Now if I shifted 3 gears (manual) and each shift takes .75 seconds (that's optimistic on a truck), would I be correct in deducting that time from the elapsed time?

so

P = 1883 / (10.055-(3*.75)) = 241KW = 323hp

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# Automotive Calculating HP from time/distance

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