Altitude correction

**jrc1122** · 04-29-2008, 06:38 PM

The track I frequent is 1285 ft above sea level = Pittsburgh Raceway Park (1/4 mile track)

I ran 13.660 @ 104.43---

according to correction - If I were sea level- I would have ran...

13.482 @ 105.80

Is it common to use the correction to determine what my cars true performance (with my driving)

Or is that the punk way out??

**Mr. Luos** · 04-29-2008, 06:42 PM

My track is 5800 feet up.

I have never claimed the corrected times.

**jrc1122** · 04-29-2008, 06:55 PM

Originally Posted by Mr. Luos

My track is 5800 feet up.

I have never claimed the corrected times.

And if anyone has a right to-- It is yall folks racing @ Bandimere-- I've ran there before (in a 2000 Hyundai Tiburon)- I ran a 17.xx-- and the funny thing is....

I raced my buddies 1995 V6 mustang-- and whopped him by a few cars every time on the streets of Aurora/ Denver.

Those were my younger days-- when I actually went out driving looking for street races... LOL @ myself.

**Mr. Luos** · 04-29-2008, 07:03 PM

Let a friend drive my '01 Grand Am GT down the track once...17.2.
Times simply suck here.

**TrickStang37** · 04-30-2008, 01:36 PM

Originally Posted by jrc1122

The track I frequent is 1285 ft above sea level = Pittsburgh Raceway Park (1/4 mile track)

I ran 13.660 @ 104.43---

according to correction - If I were sea level- I would have ran...

13.482 @ 105.80

Is it common to use the correction to determine what my cars true performance (with my driving)

Or is that the punk way out??

personally, I think all times should be corrected for weather/altitude, especially the negative DA runs. Otherwise, its just like comparing uncorrected dyno numbers.

**Firebirdjones** · 04-30-2008, 02:14 PM

Trickstang brings up a valid point. I have preached in here before about DA numbers. It's the only real way to compare tack times among people on this board that live 3,000 miles apart,,,,some at sea level and some 5,800 ft. up like Luos.

Thing is,,,,the weather is what plays a huge factor here,,,just as much if not more than your actual altitude. You can be 5,800 ft. up but you could have weather conditions that mimic 3,000 ft. or it could be worse and be 7,200 ft...

Keeping a log book of your progress with your car would only be accurate if you kept DA readings along with it. Which is why you can't rely or depend on everyones ET and MPH listed in here.

For instance here in SW Ohio we are about 600 ft. above sea level,,,,you would think that would make for a fast track,,,,,not so.
Our weather sucks throughout summer,,,,hot and humid. Mid 90's is common and the kicker is the dewpoints of 70 degrees and humidity of 90% or more. When you factor that in the DA (Density Altitude) would be somewhere close to 3,500-4,000 ft.
There are instances where the DA is very low 1,000 ft. or less,,,and sometimes a negative DA can be reached,,,but the only time we generally see that is Winter when it's very cold and dry,,,but of course the tracks are closed then

**fraz1le** · 04-30-2008, 05:03 PM

I don't think you can judge 2 car times unless the run the same night and have the same or close da. My car at my track with the same mods car run as much as .4 different from 1 friday to the next. My da was +2560 the last time I ran 2 weeks ago and I checked it yesterday because the temp had drop and pressure was up and it was +167. Is this common other places.

**Firebirdjones** · 05-01-2008, 03:50 AM

Yes. The DA changes every hour as conditions like temps, pressure, dew points, humidity go up and down.

**Johns00Z28** · 05-17-2008, 06:26 PM

Can the DA be determined before I go to the track? Is there a website to go to or something that can calculate all the variables for you and let you know what it is?

**Mr. Luos** · 05-18-2008, 05:11 PM

Originally Posted by Johns00Z28

Can the DA be determined before I go to the track? Is there a website to go to or something that can calculate all the variables for you and let you know what it is?

www.accuweather.com
http://www.modulardepot.com/density.php

**Johns00Z28** · 05-18-2008, 05:31 PM

Originally Posted by Mr. Luos

www.accuweather.com
http://www.modulardepot.com/density.php

Cool thanks, I'll be sure to use that next time I go to the track.

**Mr. Luos** · 05-19-2008, 08:53 AM

Using that....is why I can't bring myself to use adjusted ET's.

Density Altitude = 7514 feet
Uncorrected 12.0 @ 119.8
Corrected 10.69 @ 132.86

**Johns00Z28** · 05-19-2008, 08:57 AM

Originally Posted by Mr. Luos

Using that....is why I can't bring myself to use adjusted ET's.

Density Altitude = 7514 feet
Uncorrected 12.0 @ 119.8
Corrected 10.69 @ 132.86

Wow almost a second and a half and 13mph! Yeah man you need to move away from Co and get closer to sea level...lol.

**Mr. Luos** · 05-19-2008, 09:12 AM

Originally Posted by Johns00Z28

Wow almost a second and a half and 13mph! Yeah man you need to move away from Co and get closer to sea level...lol.

Someday.

I have my fingers crossed...but I am hoping to run it a few times in Texas late this year.

**Johns00Z28** · 05-19-2008, 11:32 AM

Originally Posted by Mr. Luos

Someday.

I have my fingers crossed...but I am hoping to run it a few times in Texas late this year.

That will be good, actually see what your car SHOULD be doing..lol. Where in relation to Denver are you? My sister and her husband recently moved out there and I want to say they're in the burbs but I'll have to check the name of the town.