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Just got nitro in my tires


Repsak

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Nitrogen is used in race car tires because the temperature increase during hard driving does not increase tire pressures as much as air. With air, tires with low pressure can cause heat and therefore pressure build up on the track. This effect means a car starting with a lower pressure can end up with more pressure at the end of a race than a tire that started with more pressure and therefore had less heat build up. So if you have put nitrogen in your tires without knowing why you should let it out. You are probably too slow to take advantage of it. The best thing you can do is run your pressures between 38 psi and 42 psi. This will give you better handling and braking plus less heat build up and a more constant pressure.
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I call BS. Here is the best argument I've seen (by a chemist):

 

The question about nitrogen in tires has come up in other lists on the web as well. Let me clarrify a few points.

 

1. Air is 78% nitrogen, N2, and 21% oxygen, O2. So even if you put air in the tire, it's already 78% nitrogen. Many of the so called nitrogen generators don't produce much more than 90% nitrogen.

 

2. At relatively low pressures (ie tire pressures) N2, O2 and water vapor will all behave as ideal gases, and follow PV=nRT. Pressure will increase or decrease to the same extent as the temperature increases or decreases regardless of which gas is in the tire. (Even at 300 psi, which is about 20 atm, there is little deviation from ideality.) Therefore the comments about N2 not changing in pressure as the temperature changes are without merit.

 

3. The rate of effusion (or diffusion) of a gas through a porous membrane depends on the molar mass and to some degree on the molecular diameter. N2 and O2 are almost the same size and N2 is lighter than O2 (28 g/mol vs 32 g/mol) so if either gas were to effuse out of the tire, nitrogen would do it more quickly. Luckily, tires are designed not to be porous membranes.

 

4. N2 and O2 both have essentially the same specific heat capacity, about 1.0 J/gK, and thermal conductivity, about 0.00026 W/cmK. Water vapor has a specific heat capacity of about 2 J/gK. But remember, water vapor will constitute less than 1% of the air in the tire. So the idea that N2 has different heat handling properties is also without merit.

 

5. The ozone, O3, in the atmosphere, which is a ground level pollutant, will do a great deal more damage to your tires than the O2 inside the tire. For instance, don't leave a condom out in the air in Los Angeles for a few days. It will develop lots of tiny holes and weaken.

 

spdracer22 says that dry air is preferably to air with a lot of water vapor. As a tire heats up, the very small amount of H2O present will be in the vapor state which may contribute to the overall pressure very slightly.

 

Several have suggested that N2 in a high pressure tank is more portable and requires no electricity. That would make sense, particularly for aircraft tires.

 

I find no reason to believe that N2 is going to produce a "better ride" or "better handling".

 

The bottom line is that for general passenger car tires or truck tires there is nothing to be gained (other than portability) by using nitrogen rather than air. The biggest gain will be $$$ by the companies that sell nitrogen handling equipment and the tire merchants that appeal to ignorant customers. And who is the biggest loser? Yep, the consumer.

 

Source http://www.eng-tips.com/viewthread.cfm?qid=120996&page=1 by pisgahchemist.

I believe it all comes down to moisture causing more pressure change. Dry air is pretty much indistinguishable from dry N2 in this regard.

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Nitrogen is used in race car tires because the temperature increase during hard driving does not increase tire pressures as much as air. With air, tires with low pressure can cause heat and therefore pressure build up on the track. This effect means a car starting with a lower pressure can end up with more pressure at the end of a race than a tire that started with more pressure and therefore had less heat build up. So if you have put nitrogen in your tires without knowing why you should let it out. You are probably too slow to take advantage of it. The best thing you can do is run your pressures between 38 psi and 42 psi. This will give you better handling and braking plus less heat build up and a more constant pressure.

 

 

Ding Ding Ding Ding. I didn't care to read through so many posts and i'm not sure if anyone else said this as well but This guy is correct. By keeping the tire pressure at a constant then throughout the race course the car will handle within a closer range of variability. In other words keeping one thing constant allows the driver to worry about one less thing. Like Being a chemist and being full of variable shit. Remove the shit and he'd be doing well.

 

You don't have to believe me though. Ask any real race car team.

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I call BS. Here is the best argument I've seen (by a chemist):

 

The question about nitrogen in tires has come up in other lists on the web as well. Let me clarrify a few points.

 

1. Air is 78% nitrogen, N2, and 21% oxygen, O2. So even if you put air in the tire, it's already 78% nitrogen. Many of the so called nitrogen generators don't produce much more than 90% nitrogen.

 

2. At relatively low pressures (ie tire pressures) N2, O2 and water vapor will all behave as ideal gases, and follow PV=nRT. Pressure will increase or decrease to the same extent as the temperature increases or decreases regardless of which gas is in the tire. (Even at 300 psi, which is about 20 atm, there is little deviation from ideality.) Therefore the comments about N2 not changing in pressure as the temperature changes are without merit.

 

3. The rate of effusion (or diffusion) of a gas through a porous membrane depends on the molar mass and to some degree on the molecular diameter. N2 and O2 are almost the same size and N2 is lighter than O2 (28 g/mol vs 32 g/mol) so if either gas were to effuse out of the tire, nitrogen would do it more quickly. Luckily, tires are designed not to be porous membranes.

 

4. N2 and O2 both have essentially the same specific heat capacity, about 1.0 J/gK, and thermal conductivity, about 0.00026 W/cmK. Water vapor has a specific heat capacity of about 2 J/gK. But remember, water vapor will constitute less than 1% of the air in the tire. So the idea that N2 has different heat handling properties is also without merit.

 

5. The ozone, O3, in the atmosphere, which is a ground level pollutant, will do a great deal more damage to your tires than the O2 inside the tire. For instance, don't leave a condom out in the air in Los Angeles for a few days. It will develop lots of tiny holes and weaken.

 

spdracer22 says that dry air is preferably to air with a lot of water vapor. As a tire heats up, the very small amount of H2O present will be in the vapor state which may contribute to the overall pressure very slightly.

 

Several have suggested that N2 in a high pressure tank is more portable and requires no electricity. That would make sense, particularly for aircraft tires.

 

I find no reason to believe that N2 is going to produce a "better ride" or "better handling".

 

The bottom line is that for general passenger car tires or truck tires there is nothing to be gained (other than portability) by using nitrogen rather than air. The biggest gain will be $$$ by the companies that sell nitrogen handling equipment and the tire merchants that appeal to ignorant customers. And who is the biggest loser? Yep, the consumer.

 

Source http://www.eng-tips.com/viewthread.cfm?qid=120996&page=1 by pisgahchemist.

I believe it all comes down to moisture causing more pressure change. Dry air is pretty much indistinguishable from dry N2 in this regard.

 

Ok I just got off the phone with a buddy of mine from Bow, NH. He is infact a race car engineer at RIC Racing. He states that its not the difference between Air or Nitrogen its the manufacturing process behind its bottling. Nitrogen contains nearly no water vapor when the place it into tanks. That is why nitrogen is preferred. They use nitrogen instead of all other gases that are bottled because it its the cheapest non-flamable gas. He also added that no putting nitorgen in a car which is not pushing the edge will see no net gain in using nitrogen because you're the change in psi is very minimal but, there is a change.

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Nitrogen is used in race car tires because the temperature increase during hard driving does not increase tire pressures as much as air. With air, tires with low pressure can cause heat and therefore pressure build up on the track. This effect means a car starting with a lower pressure can end up with more pressure at the end of a race than a tire that started with more pressure and therefore had less heat build up. So if you have put nitrogen in your tires without knowing why you should let it out. You are probably too slow to take advantage of it. The best thing you can do is run your pressures between 38 psi and 42 psi. This will give you better handling and braking plus less heat build up and a more constant pressure.

 

This is the reason I use it in the tires of my 911 track car. After switching to Nitrogen my cold vs off track hot pressures are now very close. The differential with normal air was way too great and caused me to have make too many adjustments.

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This is the reason I use it in the tires of my 911 track car. After switching to Nitrogen my cold vs off track hot pressures are now very close. The differential with normal air was way too great and caused me to have make too many adjustments.

 

gee i wonder what all those ex-fuking-spurts have to say about that. :lol: bosco

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