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How can you determine REAL horsepower?

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Old 08-05-2004, 03:45 PM
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Bottom line, really, is that your engine does not put out a constant hp. If all the many variables were constant, then so would the end result. Such is not the case, though. You actual hp can and will vary within a single trip.
Old 08-05-2004, 03:47 PM
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So really, are the 205, 225 240 or whatever hp cars have, is that only WOT for the first gear to second?
Old 08-05-2004, 03:49 PM
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Originally Posted by ssesc93
So really, are the 205, 225 240 or whatever hp cars have, is that only WOT for the first gear to second?
My guess is its what ever gear they pulled on the engine dyno. Most likely second.

Wait, do they even have gears on an engine dyno? Its probably just the 0 to the rev limit of the engine.
Old 08-05-2004, 06:12 PM
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Engine Dynometers just run up the revs straight. There is no gearing etc.

HP isn't a real measurement either, it'* extrapolated from Torque. When you dyno anything, you're measuring it'* torque.

Horse power is equal to ( Torque (in ft/lbs) multiplied by RPM ) divided by 5250. Thus HP will always equal TQ @ 5250 RPM. As stated HP isn't the same at every RPM.

Rated Figures would be equal to the peak Engine output, whever it would be.
Old 08-05-2004, 06:18 PM
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Originally Posted by BonneMeMN
Engine Dynometers just run up the revs straight. There is no gearing etc.

HP isn't a real measurement either, it'* extrapolated from Torque. When you dyno anything, you're measuring it'* torque.

Horse power is equal to ( Torque (in ft/lbs) multiplied by RPM ) divided by 5250. Thus HP will always equal TQ @ 5250 RPM. As stated HP isn't the same at every RPM.

Rated Figures would be equal to the peak Engine output, whever it would be.
hp is the rate/speed at which the torque is applied, correct?

If so, I'd think it'* safe to say that hp is a "real" measurement that matters... why have all the torque when it can't be applied?
Old 08-05-2004, 06:20 PM
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Yup, that'* a good way to put it
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