Air Density Calculation

I will be glad to submit any additional information needed.

Photo?

RVZ717 I will upload some pictures on sat, check the following link its our home track. Our team captured the 2008 Limited Sportsman Championship, look for the silver with blue trim #3, driver Lee Pulliam in the track pictures. This year in Late Model we need all the power we can make to compete. Thanks, J.Conway http://www.southbostonspeedway.com

Excellent find on the spreadsheet. I just briefly looked at it, but looks like just what he was after. GA

Northern Bill Great find, I have been searching off and on for a while and not found exactly what I'm looking for. I will play with this some but would like to have some more input. Is there a need to know the locations elevation for a more precise calculation? Thanks and a GA to you. J.Conway

I think not.It is included in the pressure value.An easy formula for density,0% humidity is density=P*M/R*T,M=29 for dry air.Seems page found by Northern Bill includes humidity and anything.-

ferquiza Thanks, J.Conway

The locations elevation is very important to determine jetting

If the macros are OK, he should be home free.

Charts, theories, etc., all look and sound good, but in this case you need to take most of your information from the spark plugs; "reading the plugs", in other words what the electrodes and porcelain look like. I could tell you the "colors", and so on, you really need to find someone, maybe an old timer, who will show you; plugs not only tell the mixture, they also show other factors; oil consumption, timing problems, for example you can be too lean very easy; good way to fry an engine. I would suggest for starters to have a small magnifying glass, small high intensity flash light, and LOTS of spark plugs; here again a veteran can give you an idea on heat ranges, reaches, and so on. Its not an easy, punch-it-into-the-computer answer, it will take practice and persistance, tuning makes all the difference in the world between the wanna bes and the winners. Most of all; have fun!!

I r has intellegenceintellegence I have been doing this the old school way for 40 + years and would now like to learn to be more specific. I would like to do this without buying software and utilizing the weather station and GPS for altitude I now have if possible, no monies in budget for more equipment. You seam to have a good understanding of the benefits of this and I appreciate your input. J.Conway

Hi All:

I found a hand tool for close inspection of parts like the spark plug

at the medical section of the local general store. It is a plastic tool like

the doctor checks your ears and noses with. For only around 10 bucks it

is a good tool because it has a built in light with mirror that shines onto

the area right under the lens.

Also, do you take a tissue and wipe the tail pipe after a run to see

the difference from the tissue on the run before. You can do this when

you don't have time to pull a plug and still save and engine if you start to

run lean. I learned this back in the 50's.

Meterman

P.S.That is Mass air meters

Quote:

I would like to do this without buying software and utilizing the weather station and GPS for altitude I now have if possible, no monies in budget for more equipment.

__________________________________________________________

You have a portable weather station???

If You are doing the math for calculating Air density wouldn't You only need to know barometric pressure, and be able to ignore altitude?

hey man every tuner has its own calc i need a cam spec and tracs planned to race i am a crew cheif for a busch team and run hendrick engines we have are own guidlines we also run modifieds and late models with 390s and 750s do u run a spec engine or built

Quest thanks for your input, can you explain how you do yours? We run built engines from a well established engine builder that's been around a long time and we are pleased with the performance. This is a very competitive class and I need to be sure we take advantage of everything available to me. I was a crew chief and engine tuner in the 90s for one of the last Winston cup independents. Back then Champion had a man with the knowledge to read plugs and then give you all the plugs you ever needed. He was very impressive in determining your jetting, timing, heat range, and if your cowl was working properly or manifold had problems. He used air density and experience to determine your needs. You could send a personal message if you are willing to share info you don't want displayed. Thanks, J.Conway

Hello everybody:

Well done Northern Bill, I have made some verifications of your spreadsheet and it seems to work OK. Thanks for your contribution to the Forum.

Thanks all for your input in solving my problem. I have found an engine tuners calculator that does everything I need. I enter the temperature, relative humidity, barometric pressure & actual elevation and hit calculate. It gives me Relative horsepower, air density, relative air density, density altitude, virtual temperature, actual air pressure, vapor pressure & dyno correction factor. This gives me what I need to determine the jet size if a change is indicated. With the use of this and my plug reading magnifying light I can now make precise adjustments. Again thanks to all whom contributed. J.Conway

Care to share??