Denstiy Altitude

[MADMOD]

Can anyone tell me roughly what DA is good for a NA car? I know you don't want it to high, but what about lower than your altitude? I am sure there are a ton of variables and every car is differnt but I am looking for a ball park figure. Something like if you are at a 1000 feet of altitude then for an NA car you want the DA round about 2100 ft.


Thanks

[cstreu1026]

With good weather in the fall you will see DA's below zero. The lower the better.

[MADMOD]

:confused:That is what I thought. The reason I asked if because my GM at work is a pilot and he was telling me that if he is above the DA the the plane would fly through the air easier but the engine would not make as much power. Now if you are below the DA then the engine would make more power but the plane would not fly through the air as easy. I am not for sure if that is exactly what he said but it was something along those lines.

[cstreu1026]

Well its definitely a little different for planes but that all makes sense. Denser air is harder to move through but makes more power. I am sure there is some engineer or mathematician out there that could calculate the optimum DA for a specific car but generally speaking the lower the better.

[rmracing]

If you look at the NHRA prostock guys when they go to Colorado the DA is very high out there and the cars usually slow down about 3 tenths from normal from what i remember .

[IWRBB]

The lower the better. My best times and MPH have come in "mineshaft" air. Negative density altitude. The best day was 64 degrees, 34% RH and a BP of over 30.3 in-hg. You VERY rarely see those kinds of pressures around here. Two weekends ago when I ran it was only 29.91.

[Drivermod]

The lower the better. In drag racing you will never notice the minor increase in drag due to air density. You will see a bigger affect from wind direction and will more than make up for it with the increase in horsepower.

[Timido]

The DA that we are looking at is corrected to the the weather conditions. When you run at Tristate or Edgewater the Alititude is only around 400ft. Check out my weather meter at the track sometime.

[Stangman]

So, how does one "correct" times to make up for the DA? I keep hearing about that and was curious how that works, I went with Steves LX up to Kil-Kare one day and it was about 100 degrees out and the DA was like 3400 or something like that, and I ran a 15.1 on street tires... what should that have really been in good air?

[mustang8998]

Jesse, MD has an online calculator..

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

[Stangman]

Cool, thanks Jeff, I'll check that out

Wow that is a neat toy!

So If I guessed everything right... my car should run mid 14's! woo!