well....here it is.
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From: Dallas
[QUOTE=S2oooNvegas,Feb 13 2006, 12:56 AM] i know, i was bummed, what i saw on the screen didnt come out on the print. the AF was lean. 14.67 if i remember correctly. as an average. ill be changing some more stuff soon, and going back. shootin for 240 here in vegas. wont be a problem. 
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From: SoTex
Thank you Gary, that saves me some time... one more very important thing that some people need to realize... H2O just runs in and out of the system... no chemical reactions occur with water...
COMBUSTION involves only oxygen and fuel.
COMBUSTION involves only oxygen and fuel.
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The amount of mis-information on this subject is almost funny. I have to agree with gary PHD on sveral points. I also have a PHD in chemistry.
The higher altitude you go to, the less oxygen molecules there are per unit volume (say meters cubed) for your engine to react with fuel to produce power ie less power at higher altiltude. Making more power at sea level is due to the lower altitude.
The cooler the air, the more power you will make. Cooler air is more dense than warmer air, and has more oxygen molecules per unit volume. Add to that, that cooler air is also cooler, so it helps keep the engine temps down, allowing you to add more fuel, allowing you to make more power.
Hot air can hold more water than cold air. Which is why we use relative humidity.
The colder the air the less water it can hold. Would you rather have hot humid air to make more power or cold humid air? Answer, cold humid air.
Cold dry air vs cold humid air? Not much difference as cold air holds feck all water in the first place
The humidity in air does not provide a significant cooling effect like water or alky injection as far as I am aware.
The injection systems provide a very fine spray of those liquids (atomiaztion or neublization) which provides cooling and helps stop preignition. It does this by using the latent heat in the cylinder to convert itself from a very fine liquid drop into a vapor. This requires the input of energy which is supplied by the combustion chamber. This energy is called "the latent heat of vaporization". This cools the cylinder.
It is the same as taking water at 99.9 deg C and heating it to make steam at 100 deg C. It requires much more energy than what you would expect to rise the water 0.1 deg C
This is also the reason why steam at 100 deg C will give you a much nastier burn than water at 99.9 C. The steam releases alot of heat energy as it undergoes a phase change to liquid at 99 deg C, and then contiunes to burn you like hot water.
All the humidity in the air does is occupy space that the oxygen molecules and nitrogen molecules could be occupying, ergo less O2.
Think about it like this. Take one balloon full of dry air (like me) and add water vapor. The balloon has to expand to allow the vapor in, for the pressure to remain constant. There is now the same amount of o2 in a bigger volume, which eqauls less air for your car per unit vol
In summary
Cold dry places close to sea level are good places to get more power from you car.
Cold humid places close to sea level dont really exist on earth (ireland and seattle may be the exceptions) but are good places to get more power from you car (prolly less than the above example)
High altiude places suck for power. The humidity is less of a factor for power, but very cool temps will help you regain some of that lost power
The higher altitude you go to, the less oxygen molecules there are per unit volume (say meters cubed) for your engine to react with fuel to produce power ie less power at higher altiltude. Making more power at sea level is due to the lower altitude.
The cooler the air, the more power you will make. Cooler air is more dense than warmer air, and has more oxygen molecules per unit volume. Add to that, that cooler air is also cooler, so it helps keep the engine temps down, allowing you to add more fuel, allowing you to make more power.
Hot air can hold more water than cold air. Which is why we use relative humidity.
The colder the air the less water it can hold. Would you rather have hot humid air to make more power or cold humid air? Answer, cold humid air.
Cold dry air vs cold humid air? Not much difference as cold air holds feck all water in the first place
The humidity in air does not provide a significant cooling effect like water or alky injection as far as I am aware.
The injection systems provide a very fine spray of those liquids (atomiaztion or neublization) which provides cooling and helps stop preignition. It does this by using the latent heat in the cylinder to convert itself from a very fine liquid drop into a vapor. This requires the input of energy which is supplied by the combustion chamber. This energy is called "the latent heat of vaporization". This cools the cylinder.
It is the same as taking water at 99.9 deg C and heating it to make steam at 100 deg C. It requires much more energy than what you would expect to rise the water 0.1 deg C
This is also the reason why steam at 100 deg C will give you a much nastier burn than water at 99.9 C. The steam releases alot of heat energy as it undergoes a phase change to liquid at 99 deg C, and then contiunes to burn you like hot water.
All the humidity in the air does is occupy space that the oxygen molecules and nitrogen molecules could be occupying, ergo less O2.
Think about it like this. Take one balloon full of dry air (like me) and add water vapor. The balloon has to expand to allow the vapor in, for the pressure to remain constant. There is now the same amount of o2 in a bigger volume, which eqauls less air for your car per unit vol
In summary
Cold dry places close to sea level are good places to get more power from you car.
Cold humid places close to sea level dont really exist on earth (ireland and seattle may be the exceptions) but are good places to get more power from you car (prolly less than the above example)
High altiude places suck for power. The humidity is less of a factor for power, but very cool temps will help you regain some of that lost power
Thread Starter
Joined: Sep 2003
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From: las vegas
Originally Posted by kumar75150,Feb 13 2006, 07:21 AM
those are good numbers but look at the top right next to "CF: "
1) they are corrected
2) they are STD and not SAE corrected
SAE is the proper correction factor to use and yields lower numbers than STD correction. So your numbers are a little inflated.
Either way, your car should be making 215+ rwhp which is strong but still not enough to pull on M3s and C5s etc
what are your mods again? My stock AP2 with 100 miles dynoed 204.5 rwhp SAE corrected.
1) they are corrected
2) they are STD and not SAE corrected
SAE is the proper correction factor to use and yields lower numbers than STD correction. So your numbers are a little inflated.
Either way, your car should be making 215+ rwhp which is strong but still not enough to pull on M3s and C5s etc
what are your mods again? My stock AP2 with 100 miles dynoed 204.5 rwhp SAE corrected.
Thread Starter
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From: las vegas
Originally Posted by brent_strong,Feb 13 2006, 07:50 AM
395ft/lbs...is that where the dyno operator blipped the throttle on decel to bump the numbers up? 
laters
Thread Starter
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From: las vegas
Originally Posted by emerilmemorex,Feb 13 2006, 07:48 AM
More lies and stupidity from the Vegas crew...
Humidity makes power, what the hell????
Hackmac you are a mechanic? eek! Stay away from that dealership!
Tools, the lot of you.
Humidity makes power, what the hell????
Hackmac you are a mechanic? eek! Stay away from that dealership!
Tools, the lot of you.
