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How can you determine REAL horsepower?

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Old 08-05-2004, 03:16 PM
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Default How can you determine REAL horsepower?

I see heat play a big role, altitude and cold air but what is the real hp for cars and the 0-60 times? I remember posting the 92 SSEi Road & Track page and the 0-60 in 9.0 sec was wrong, so what is it? Also is 240hp the right hp and 6.6 0-60 right for a stock GTP?
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Old 08-05-2004, 03:24 PM
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well, f/i cars tend to run much better when its cool and dry... the only problem is when it is cold, traction is much more limited... say on liek an 80 degree day i run a 15.0 @ 93 with a 2.2 r/t. on a 50 degree day, you may see .1- .2 quicker, but at maybe 95.5, with a 2.4 r/t.



hmm, none of that really has anything to do with what you asked.... sorry!!!
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Old 08-05-2004, 03:27 PM
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Thats what I was talking about. How can you actually get the truth on hp? Its seem as if its an estimate. All about the weather. That means the maybe bonnies have either more or less hp than what they say?
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Old 08-05-2004, 03:56 PM
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Calculate HP From ET and Weight
HP = (Weight / ((ET/5.825)^3))

Calculate HP From MPH and Weight
HP = (((MPH / 234)^3) * Weight)

horsepower = mep x displcement x rpm / 792,00

taxable horsepower = bore2 x cylinders / 2.5

weight transfer = weight x cg height / wheelbase x g

lateral weight transfer = weight x cg height / wheel track x g
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Old 08-05-2004, 04:18 PM
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Originally Posted by TrueWildMan
Calculate HP From ET and Weight
HP = (Weight / ((ET/5.825)^3))

Calculate HP From MPH and Weight
HP = (((MPH / 234)^3) * Weight)

horsepower = mep x displcement x rpm / 792,00

taxable horsepower = bore2 x cylinders / 2.5

weight transfer = weight x cg height / wheelbase x g

lateral weight transfer = weight x cg height / wheel track x g

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Old 08-05-2004, 04:20 PM
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Short-circuiting there??
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Old 08-05-2004, 04:23 PM
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Thanks, Jim. Those formulas will probably land you within 5%. They're well established and proven.

There are some Java calculators out on the web for this information Steve!

Makes it easier
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Old 08-05-2004, 04:30 PM
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what does ET stand for, estimated time?
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Old 08-05-2004, 04:33 PM
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Old 08-05-2004, 04:41 PM
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Engine dyno to be exact. Wheel dyno + the knowledge of your drivetrain loss will get you close. Track time and the formulas above will help as well but there are alot of variables with track time (humidity, temp, launches, etc...)
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