How many of you inflate your tires with nitrogen?

 

[quote]Originally posted by 993RS:
<strong>How many of you inflate your tires with nitrogen?</strong><hr></blockquote>

Wouldn't helium be better? Might make your car seem like it's floating

 

I know the F1 boys use Nitrogen because it doesn't expand (much) as you increase temperature, hence more stable tyre pressure.

I guess it would be useful for trackdays (DE's) but I wouldn't have a clue where to get my tyres inflated with it.

 

AFAIK, the main reason to inflate the tires w/nitrogen is to reduce the amount of moisture in the inflated tire hence reducing the tire pressure change with change in tire temperature.

Wouldn't skipping the sandwich be more effective than weight reduction/lift from use of helium.

 

How about propane instead.
After the race, you can cook yourself a nice burger!

 

This issue continues to puzzle me. All gasses expand with increased temperature (remember PV=nRT?). Air is 80% nitrogen already. I don't to believe that inflation with nitrogen is going to make a siginificant difference to any conditions we are going to see. Maybe in F1 where really small changes count (and I'm skeptical here too), but not in p-car racing.

If you are worried about moisture you can dry the air used in inflation as easily as drying the nitrogen.

 

Lots of tire shops here in Switzerland offer it. As far as I understand it: It also does not react with rubber. Tire pressures have to be adjusted less often, tread mileage and fuel economy will improve and overall tire life should be extended. It should also put an end to rim corrosion. I have just started using it and am curious to see if any of these benefits are evident.

 

[quote]Originally posted by Tom W:
<strong>This issue continues to puzzle me. All gasses expand with increased temperature (remember PV=nRT?). Air is 80% nitrogen already. I don't to believe that inflation with nitrogen is going to make a siginificant difference to any conditions we are going to see. Maybe in F1 where really small changes count (and I'm skeptical here too), but not in p-car racing.

If you are worried about moisture you can dry the air used in inflation as easily as drying the nitrogen.</strong><hr></blockquote>

You are correct. There is no differnece in the pressure characteristics between dry air, dry nitrogen or any other dry gas. The advantages of nitrogen include; 1) You know it is dry 2) easier to haul around in a trailer than a compressor 3) Instant high pressure - no need to wait for a compressor to build pressure.

 

FWIW

On really, really big tires (like on mining trucks or rubber tire earthmovers), nitrogen is used as it is an inert gas and will not explode or feed a fire. I know of a case where a very large replacement tire was fitted to a mining truck. The mechanic failed to notice a 2 x 4 that was in the tire during shipping. The tire was installed and filled with shop air. As the truck acquired more miles, the 2 x 4 was reduced to sawdust. Eventually, the temperature of the air inside the tire was great enough for the air / sawdust mix to spontaneously combust. The big bang that resulted blew the floor of the cab up into the roof, crushing the operator. On these big tires, you never, ever use shop air. only nitrogen

 

Compressed nitrogen contains less moisture than compressed air. When the tire heats up, moisture in the tire vaporizes and expands, causing the pressure inside the tire to increase.

 

I use Nitrogen in my track tires. My mechanic brings along cylinders to run his impact tools, so it's readily available (I fill a small 4 gal. tank for my use).

Nitrogen is dry, which means less pressure increase with heat. But N. also registers the heat-induced pres. more quickly, so you can more quickly adjust pres. and get more consistency over time.

 

Phil
If your assertion that "tread mileage and fuel economy will improve and overall tire life should be extended" is premised on a comparison of consistently properly nitrogen inflated tires vs. underinflated (i.e., unadjusted for leakage) air filled tires it is correct. However, I just don't believe it's a real world street driving issue for people who regularly check inflation pressures, especially since even nitrogen filled tires are subject to temp related pressure changes and mechanical leakage.

There is no question nitrogen will retard or prevent the gradual oxidation & resulting chemical degradation of the tire rubber from oxygen percolation over (a very long) time. Tires have a lining, as well as antioxident compounds, designed to prevent oxygen from attacking the rubber. Over time the lining will be compromised & the antioxidents will become exhausted permitting oxygen to attack the rubber resulting in a loss of effectiveness. However, for other than extremely low mileage drivers the tire tread will be worn away from use long, long before it's chemically destroyed.

Nitrogen will prevent rim oxidation (corrosion) which is not just unsightly to the tire changer, but also produces a very fine dust (aluminum hydroxide in aluminum wheels).

AFAIK most military aircraft & commercial airlines use nitrogen, but I think that's for issues related to combustibility at very high pressures & temps (altitude related) from interaction of the oxygen and tire hydrocarbons.

So what do the "experts" say about the pressure issue:
<a href="http://cartalk.cars.com/Columns/Archive/1995/March/07.html" target="_blank">Click & Clack - CarTalk</a>

 

Hey Fred - a bit off topic (actually very much so), but I notice you are from the "pumpkin capital of the world" - where is that. Tom W and I hail from Half Moon Bay, which also makes this claim.

 

Several locations claim to be the "Pumkin Capital of the World", but only Morton, Illinois has the mighty Q-36 pumpkin chucker in its arsenal. We stand ready to meet any and all challengers.

<a href="http://www.douglascoulter.com/body_punkin__chuckin_.html" target="_blank">Q-36 Pumpkin Chunkin</a>

You know you live in a small town when the biggest event is a pumpkin festival!

 

Well Fred you defintiely have us in Half Moon Bay beat - although we do hold a mean pumpkin festival that usually attracts around 300,000 people to a town of 12,000 for one weekend. We may be able to crush you with one of the 1,000 pound pumpkins that show up to win the pumpkin contest, but I do not see how we could get inside the defenses provided by your 700 MPH pumpkin cannon.