Is nitrogen really better?

<div class='quotetop'>QUOTE(paprius4030 @ Sep 23 2006, 10:25 AM) [snapback]323860[/snapback]</div>

I think most will agree it's pretty much a gimmick. If I recall correctly, if you put nitrogen in your tires, they will be less susceptible to changes in pressure due to changes in temperature. This is why nitrogen is usually used in racecar tires--the pressure remains more constant even when they are very hot going 200 mph. Save your money, stick with air, and just check it once in awhile

 

<div class='quotetop'>QUOTE(paprius4030 @ Sep 23 2006, 10:25 AM) [snapback]323860[/snapback]</div>

Nitrogen is an excellent material for your tires. I have a machine that lets me inflate tires using a special mixture of 78% nitrogen and other secret ingredients. If you are not getting my joke/sarcasm, ask your local scientist/google what air is made out of. I hope they are not charging too much for this special nitrogen service.

 

Snake oil! Air is mostly nitrogen. The two main advantages to pure nitrogen are that it doesn't support combustion and it is dry, so you don't have water vapor messing with tire pressure. Dry air would work just about as well at keeping pressure in the tires, and tire fires are not a big problem for normal driving. What's more, the devices used to fill tires with nitrogen at tire stores don't use pure nitrogen, they just increase the concentraition from normal air. Save your money, or better yet, send it to me.

Tom

 

Race car teams use nitrogen. The reason they do is mostly because the nitrogen is both inert and dry. As the tires heat up to race temperatures, the dry nitrogen expands in a predictable manner, more so than compressed air.

As far as using it in street tires, there's no harm but I sure wouldn't pay extra for it. The benefits are SO minor on the street that you would never notice them.

 

<div class='quotetop'>QUOTE(qbee42 @ Sep 23 2006, 02:51 PM) [snapback]323967[/snapback]</div>

Nitrogen doesn't expand/contract like so you basically don't need to check your pressures so aften and with places like Costco giving it for free with a set of new tires what's the big deal?

 

<div class='quotetop'>QUOTE(BobZ @ Sep 23 2006, 01:12 PM) [snapback]323975[/snapback]</div>

Don't think that's correct. Anyone want to look it up? My experience has been that dry nitrogen expands with heat slightly less, and more predictable than air. It's also less corrosive, but of course the effects of the outside world on the outside of the tire are way more corrosive than the air inside the tire.

 

<div class='quotetop'>QUOTE(narf @ Sep 23 2006, 03:25 PM) [snapback]323981[/snapback]</div>

You should have looked it up yourself before putting your foot in your mouth

http://www.local6.com/news/8459725/detail.html

http://www.buywheelstoday.com/info/?id=45

http://forums.dealmac.com/read.php?1,2425939

 

<div class='quotetop'>QUOTE(BobZ @ Sep 23 2006, 01:06 PM) [snapback]323999[/snapback]</div>

A local TV news program in Florida, a tire dealer and a poster on an internet message board?



Those are not exactly definitive, authoritative, credible sources to support such a blanket indictment of someone else' opinion.

 

<div class='quotetop'>QUOTE(BobZ @ Sep 23 2006, 03:12 PM) [snapback]323975[/snapback]</div>

Nitrogen expands and contracts pretty much the same as plain old air; for that matter, air is 78% Nitrogen. Water vapor makes the bigger difference, since water vapor is a non-ideal gas. Dry air will work almost as well as dry Nitrogen. The "Nitronized" fill provided by tire shops is not pure Nitrogen. It is a higher percentage of Nitrogen, and presumably is drier than plain air, but not enough to make any real difference. It's still snake oil.

Tom

 

<div class='quotetop'>QUOTE(IsrAmeriPrius @ Sep 23 2006, 09:31 PM) [snapback]324086[/snapback]</div>

Run a google on nitrogen in tires and maybe you'll learn something. The government will be requiring all new cars to be equipped with TPMS in the next year or two because better that 50% of the cars on the road are being driven with under inflated tires. Nitro is idea for the slackers who never check pressures

http://www-nrd.nhtsa.dot.gov/vrtc/ca/tpms.htm

 

<div class='quotetop'>QUOTE(qbee42 @ Sep 24 2006, 01:12 AM) [snapback]324149[/snapback]</div>

Not true. Nitro is not so temperature sensitive as air thus there is little to no pressure fluxuations. Geez on a forum where everyone looks to squeak every last MPG out of these cars you'd think there'd be more support. Again go run a google and learn more about this. NASCAR uses it, Gov uses it, Buses use it even the space shuttle.

Snake oil?! Gbee it's that kind of closed minded thinking unable to accept change that put Ford Motor Co. where they are today

 

<div class='quotetop'>QUOTE(BobZ @ Sep 24 2006, 08:22 AM) [snapback]324202[/snapback]</div>

You don't need google, just get out your copy of the CRC Handbook of Chemistry and Physics. You'll find that air and Nitrogen's coefficient of thermal expansion is almost equal. As I said before, it's the water that causes the difference in pressure swings. Physics is more trustworthy than the Internet, but here is a link for you: http://www.cartalk.com/content/columns/Arc...ptember/05.html . I'll copy the text below:

Dear Tom and Ray:


I heard a story on my local NPR station about a place in Houston where car owners can have the air in their tires replaced with nitrogen at a cost of $100. This service is advertised as a fuel economy enhancement because nitrogen diffuses through the tire at a slower rate than air, and so the tires stay at the proper pressure longer. Is this a scam, or what? -- Mark

Ray: Yes. And a very clever one at that. In fact, my brother's on the phone right now seeing if we can get the local nitrogen-transfusion franchise around here.

Tom: Their claim that nitrogen keeps your tire pressure more constant is actually correct. But their reasoning is wacko. It has nothing to do with diffusion of air through the rubber.

Ray: The reason nitrogen pressure stays more constant than air pressure is because air contains water vapor, and so it expands less predictably than nitrogen. There's a different percentage of water vapor in the air on any given day (a k a the humidity), so you never know exactly how much tire expansion you'll get from the water vapor.

Tom: It's not enough expansion for you or me to notice, but some race-car drivers notice it. Formula One (i.e., Indy 500) racers use nitrogen in their tires because when you're traveling around an oval track at 200 mph, you want your tire pressure to be entirely predictable. They even "stagger" the tire pressure on those cars, making the outside tires a little fuller than the inside tires to keep the car turning inward. And at those speeds, an eighth of an inch in tire height can make a huge difference.

Ray: But for you and me (and everyone else reading this column today), Mark, it makes absolutely no difference at all. And it's simply not worth it (unless, of course, you can steal the nitrogen from work!).

Tom: Seriously, you can keep your tire pressure constant enough for street and highway driving by simply checking it periodically.

 

Hey Dr. Z, maybe you should take a deep breath and count to ten or something. I'm assuming that your stress is due to Chrysler cancelling your ad spots. Or maybe you just invested in some nitrogen supply venture and you hate to hear any criticisms.

I would think that your tire retailer might have been the best authority on the use of nitrogen to inflate tires, but then they said "Pure nitrogen does not contain moisture: Compressed air contains oxygen and therefore water vapor." They got the part right about nitrogen being dry, assuming that they are using pure nitrogen. However, the fact that standard air has oxygen in it has nothing to do with the moisure content. It is quite possible to have very dry compressed air, regardless of the oxygen content. It might be interesting to run a comparison test with tires filled with pure nitrogen, dry compressed air (scuba bottles as one source), and normal gas station quality compressed air.

(I'd put my money on there being no real difference)

 

<div class='quotetop'>QUOTE(8AA @ Sep 24 2006, 11:41 AM) [snapback]324259[/snapback]</div>

I crew on a Grand American racing team (teamcobaltcalifornia.com). We spend a lot of money keeping nitrogen cylinders on hand to inflate our tires. Pure (or nearly pure Nitrogen) doesn't absorb water, there is no oxygen to react with the hot rubber (not that significant). The bottom line is that there is very little increase in Tire pressure at the extremely high temps that racing tires run at. We don't need screwed up tire geometry and blowouts in a race.

Whether this translates into any change in MPG on Prius - I don't know. But there are quite a few bizarre things that I see on PriusChat that people do and swear that they've improved their MPG. Certainly it would spell and additional measure of safety for the lunatic fringe that inflate their tires to 100 PSI.

 

<div class='quotetop'>QUOTE(8AA @ Sep 24 2006, 11:41 AM) [snapback]324259[/snapback]</div>

You make little to no sense Especially since I work for Cadillac not chysler and since Cadillac warrantees our own tires in house I guess that makes me the tire retailer. The bottom line is Nitro is not snake oil it's a viable option. It's use is growing and you apparently don't like to be disagreed with.

I like that ten year old link Gbee $100 to fill your tires hahaha Get real. Costco gives it to you free with a set of tires.

 

<div class='quotetop'>QUOTE(BobZ @ Sep 24 2006, 01:33 PM) [snapback]324312[/snapback]</div>

He was making a joke... have you ever seen the Chrysler commercials with DCX chief Dr. Z?

 

<div class='quotetop'>QUOTE(LaughingMan @ Sep 24 2006, 01:36 PM) [snapback]324314[/snapback]</div>

No kidding.

 

<div class='quotetop'>QUOTE(BobZ @ Sep 24 2006, 10:33 AM) [snapback]324312[/snapback]</div>

Agreed. Nitrogen is not snake oil and it is a viable option, especially since it is free at Costco, but not for the reasons that you have stated.