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What would be the effect of humidity in a cars performance?

I am getting 0-60 4.71 and 1/4 mile [email protected] with a Temp of 76F and dew point 73F, humidity about 89%. Yes using the G-tech...



I think this is a huge factor to deal with...

Thanks
 

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This is just from my SOTP meter but I could really tell how much more sluggish my 99 was when it was humid out. To me it was very similar to a 20-30 degree temperature increase.

- Charley
 

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The Highlander said:
What would be the effect of humidity in a cars performance?

I am getting 0-60 4.71 and 1/4 mile [email protected] with a Temp of 76F and dew point 73F, humidity about 89%. Yes using the G-tech...
There are three parameters that affect air density. Barometric pressure is the most significant, temperature is next, and relative humidity is the least. Changes of .1 in hg baro, 2 F temp, and 5% RH will change performance.

I noticed you didn't quote the baro pressure. You really need to gather that info too.

Another thing I noticed is that the dew point was within 7 to 10 F of the temp. That means ~ 100 grains of water vapor in the air. Combustion speed/quality is affected by this amount of water resulting in reduced power. This phenomenon is not documented in the SAE stuff but is practiced by most pro race teams. Back in '92 I was invited to the Gaerty Engine shop north of Indy. Earl has a temp/humidity controled dyno cell. We flogged a $30,000 (in then year dollars) methanol sprint car motor for 2 days to define this condition.

Get yourself a good weather station.

www.computechsys.com

If you have the three input items, I will gladly calculate the correction factor for you. The equations are a little complicated because you have to use steam talbe data to determine RH affect.
 
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