How much can Humidity slow down a n/a car?

xtweakerx

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wondering if its say about 84% Humidity 79 degree's but feels like 84.

Can that have an impact of slowing a car down a tenth or two vs.

when its like 54% Humidity and 70 degree's out.


could it make the difference of going 13.20 in 84% Humidity and going 13.00 in 54% Humidity?
 

ArtQ

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Temp, humidity/dewpoint are factors in determining density altitude.
Density altitude (DA) is a measure based against standard day conditions at sea level. For simplicity sake, positive DA=lower performance, negative DA=improved performance. (See above sticky for more info)

As a rule of thumb multiply .0001 times current DA and this will give you a correction:
Last week you ran a 12.5 at a +1200 foot DA
This week you ran a 12.38 at a +0 foot DA

Factoring in the fact that you drove the car exactly the same and the track conditions were identical the effect of the lower DA is why you ran faster.
 

xtweakerx

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sick, i also found this cool site http://www.modulardepot.com/density.php?show=density


i plug in all my values and it corrects the time.

i was down on myself for going 13.20's last night but i was realizing it was VERY Humid and hot, 80 F w/ 79% humidity etc.

i plugged all my values in and my 13.20 turned into a 12.99.. now i have to hope for a nice day in FL so I can actually do it. lol
 

chad05gt

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But... you run what you run where you run.

But... you run what you run where you run.

Trust that people that race are well aware that a 13.5 car in colorado IS a fast car...
 

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