Weather Conditions vs. ET's
05-30-2002, 12:57 PM
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Melting Slicks
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Weather Conditions vs. ET's
Can anyone point me to the equation(s) for calculating the effective height above sea level vs. the prevailing atmosheric conditions (baro. pressure, temp. and himidity)? I just ran in 80 degree, 73% humidity and low pressure to the east. I was wondering how it affected my times. By asking this question, you can guess they were not very good. My 60 ft times were 1.8's but my ET was no better than 8.14 @ 85 mph.
05-30-2002, 10:41 PM
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Re: Weather Conditions vs. ET's (RWhite)
Buy yourself a weather station. I'm sure it can be done manually, but the weather station does it for you. NHRA has correction factors for altitude adjustment, but they're only for the physical altitude of the track, not for the "density altitude". Altronics offers as a "ball park" example, 200 feet difference in DA equals approximately a hundredth in the quarter.
05-30-2002, 11:06 PM
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05-31-2002, 12:12 AM
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Melting Slicks
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Re: Weather Conditions vs. ET's (REDGAR)
Thanks guys for the info. I also found this about density altitude calculation.
http://rshelq.home.sprynet.com/
This has a bunch of neat calculations that can relate your weather conditons at the time of a race and how it affects your ET's.
http://rshelq.home.sprynet.com/
This has a bunch of neat calculations that can relate your weather conditons at the time of a race and how it affects your ET's.