Density altitude (Tulsa ok.)
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Density altitude (Tulsa ok.)
I ran my car on june 20, 12.65et.Temp 71, hum.55, BP 29.85 I was given a program to find the density alt. 1166ft is what I got.Made some changes.Ran july,19 12.67et ,temp 80, hum72, BP 29.89 Density alt.1841.Did the changes help and the air slowed the car down?
- Stan Weiss
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While the changes in conditions would have produced a change in air density of -2.4%, that does not mean that power will be reduced by 2.4%.
Air density and power do not correlate exactly. Neither does air density and mixture. In your case the change in air would have reduced power by .67%.
In addition, air density has an effect on vehicle speed due to change in aerodynamic drag forces.
Air density and power do not correlate exactly. Neither does air density and mixture. In your case the change in air would have reduced power by .67%.
In addition, air density has an effect on vehicle speed due to change in aerodynamic drag forces.
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- Stan Weiss
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Based on the 2006 FORD Performance Parts catalog that would be SAE J607. Original run correction 1.032908 (VP 0.420066) later run correction 1.05549 (VP 0.741798) difference 0.022582 or 2.2582 %. The only thing that I can think of is that one of us coming up with the wrong corrected Barometric Pressure / Vapor Pressure.
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- Stan Weiss
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- Stan Weiss
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Sometimes I just what is not there. I just check the formula for the forth time A^1.2 * B^0.6Stan Weiss wrote:Dave,
I am using this formula A^1.2 * B^0.5. I just noted that the 2006 FORD Performance Parts catalog calls that SAE J607. For the Original run I get a correction of 1.032908 (my Vapor Pressure 0.420066). For the later run I get a correction of 1.05549 (my Vapor Pressure 0.741798).
Stan
You might want to browse around and look at the calculators this guy has for figuring air density and relative power output. He has detailed explanations for how the math is done as well.
He is a professional engineer and knows his stuff on this subject.
http://wahiduddin.net/calc/calc_hp_dp.htm
Larry
He is a professional engineer and knows his stuff on this subject.
http://wahiduddin.net/calc/calc_hp_dp.htm
Larry