Nitrogen in tires???

The latest fad here seems to be fill your tyres with nitrogen. The sales pitch claims better tire pressure consistency when hot and up to 30% increase in tire life. Apparently they use it in Nascar as well. Anybody using it over there and to any great effect?

EBC brake pads are also being touted as the best thing since sliced bread, no brake dust, squeeling and better when hot than standard brake pads. Anyone out there had positive results and if so is it the green stuff or the red stuff?

Everybody's tyres already have more than 70% nitrogen in them, assuming regular atmospheric 'air' was used to inflate them ... sounds like some serious HYPE to me! Hydrogen sounds like the ticket!

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Warren Hall
1973 911S Targa

Nitrogen is a plus, no doubt about it. The thermal stability makes it much easier to work with tire pressures. Some folks think that reducing the tire pressure in race / performance tires increases the contact area. While this might be true at first, once the air in the tire is heated, it expands, which rapidly puts the tire back to its normal psi range of operation. Nitrogen does not heat as easily, meaning you can leave your tires at the pressure they were designed to work at without compensating for the many unknown variables in the Porsche world.

Hydrogen is flammable (a la Hindenberg), but Helium would be just the ticket for decreasing unsprung weight

I read that it is a combination of nitrogen and oxygen. I doubt there is an increase by 30%. Rubber wears out no matter what. If a person checks their pressure on a weekly basis, wear will not be a prob. Nitrogen is a cooler gas. That's why it is used in nitros injected cars with little pinging.

When you see the price of a tank of high pressure nitrogen, and the regulator required to use it, you'll soon forget about this idea.

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Doug
'81 SC Coupe (aka: "Blue Bomber")
Canada West Region PCA
members.home.net/zielke/911SC.htm

Hey... hydrogen is the ticket! When you have a blowout, it REALLY blows.
regards,
jlex.

Yeah, it's convenient that way - it cleans the rim off and blows out the carbon (based life form) as well!

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Mark Szabo
1986 911 Targa 3.2
1987 Escort 5-speed 1.9 RIP
The Porsche Owners Gallery

If anyone does get the bright idea to try this then make sure you know what you are doing.I have a friend that was almost killed by a apprentice filling a aircraft tire.The apprentice is permanently deaf and my friend was working at a table 35 ft away when the shrapnal from the exploded tire and rim hit the table and drove him and the table into a wall 5ft behind him breaking both his legs,ribs etc.very dangerous stuff in the wrong hands.

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Grant 75 911s targa

The reason why aircraft tires can explode with such force is because of the very high pressures they run. For example, a Dash-8-400 mainwheel is serviced to about 227psi. That's a wee bit higher than what you would want to see in a car tire. So it's not the nitrogen that's dangerous, it's the pressure.

As far as using it in your car, I agree with Warren. The air you're breathing right now is already seventy percent nitrogen. Unless the tire you're filling is attached to a massive multi disc carbon brake which needs to bring tens of thousands of pounds to a stop in a hurry, there's no real advantage.

But hey, if you can get your hands on some nitrogen and the proper regulator to fill your tires to the correct pressure, give it a try. It can't hurt. Just don't spend any crazy money because I don't think you'll see any difference.

Wow. 227psi. The 727-200 uses about 100-105 psi of nitrogen in the front, and 145psi in the main. Aircraft use nitrogen in the tires. They won't use anything else.

True, air is 70% nitrogen. But it also contains moisture and the moisture aids in the pressure increase due to temperature. Most racecar teams use nitrogen because it's dry and can be used in air tools (2 birds).

I use nitrogen in my race car tires. I can tell you that although I still get a pressure rise (8#), it is not as great a rise as with air and the tires warm up quicker. I get a more predictable pressure increase and the tires are warm in one lap.

I see no increase in tire life.

Doug '84 911 ROW (Lauren)
#89 Spec Racer Ford (David)

Don't know much about the helium (F1 does it) nitrogen, etc. I can tell you that the EBC Green pads are much cleaner than my stock pads. They feel a bit mushier and have a rep for warping rotors (slightly did so to my car ). I did this change on my BMW. If I had to do it again, I would stick to stock pads.

Dug89 is right on. It is the moisture that is present in the compressed air that turns from liquid to steam resulting in a hugh pressure increase. In addition it is a fire thing. Those huge tires you see on earth moving equipment are required be filled with nitrogen. Why? Because those huge tires with the incredible loads can flex enough to get so hot as to ignite. The oxygen in the air can support an internal fire, nitrogen can't. Seems like a good safety thing for extreme conditions!

Diverdan

are you people for real?

just drive to your gas station and fill your tires...what's the big deal?


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83 sc euro cab

What gas stations have the best air?
Is it true that the base air is the same at all gas stations, with the only difference being the additive packages?

I think Amoco Silver Premium Grade Air is the most reliable and consistently highest performing tire air when tested on a track environment. ...And they only charge $0.25 for 5 minutes worth! What a value!

And while your filling those tires with Nitrogen...don't forget to repack your muffler bearings.



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_ _ __ _ _
Nick Shumaker
1982 911SC Coupe
nickshu@yahoo.com
PCA -- Rocky Mtn. Region

Everyone knows the real secret behind gaining additional speed is to lighten the car's weight.... that's why I fill my car's tires with helium.... have to keep off the roads on windy days, though.
regards,
jlex.

Doug89 and and diverdan got it right. While normal air is indeed 78% Nitrogen it also has other components. As related to tires the worst of these is water. This water in the compressed air(those of you with compressors know what I am referring to) in your tires causes the pressures to fluctuate MORE with varying temperature than pure nitrogen(with ~0% water content)from a bottle. So to stabilize pressures and inhibit corrosion due to moisture use bottled nitrogen. Any inert gas of course would do, nitrogen just happens to be dirt cheap and widely available.

DUG89 is absolutely correct in his reasoning why all race cars use N2 in their tires.

Guys who are getting as serious as you can about track tuning can benefit from N2 due to the predictable pressure rise going from cold to hot.

If you are just driving on the street than it would be no benefit at all, since you are never running your tires at a consistent temperature.