Background: I play paintball, which means I have both a 4500psi, 68ci carbon fiber air tank and a regular 50lb nitrogen steel tank. For purposes of tire pressure the important thing is no moisure gets into the tire--at least that's my understanding of why NASCAR crews fill tires with nitrogen. Nitrogen itself isn't better than high pressure air, it's just easier to get.

So it occurred to me that for a minimal cost (regulator and hose fittings for CF tank, hose fittings for steel tank) I could run nitrogen in the tires and use the CF tank at events to top off air pressure.

The small size and light weight (5 lbs) of the CF tank is an obvious advantage on grid. My question is would running moisture-free nitrogen in the tires be of any benefit at autocross or track events? Or are the runs too short for any real benefit to occur?

One of the tire places I use fills the tires with nitrogen. It supposedly is more resistant to temp related volume changes. So your tire pressure doesn't rise as much after heating up.

just plain old air is 78% nitrogen. in fact to make liquid nitrogen they cool air (my dad told me this).

i thought boyles law says expanding gas expands the same amount no matter what it is. been a while since chem class tho :)

james

Originally posted by Ophitioxaemia
i thought boyles law says expanding gas expands the same amount no matter what it is.
[sigh] Please re-read the second sentence of my original post. It's surprising how many people across several forums have missed that point.

sorry, i was responding to a *response* to your post, you were indeed clear about what you meant. :)

all the national champions in my region use just plain old air. i know, ive borrowed andy mckee's air compressor before. :D

james

I say any benefit is a real benefit. Practicing with, and then running on Nitrogen will probably give you, if not better, then, more consistent times and your car will more predictable if you don't have to worry about changes in tire pressure.

to recap: nitrogen will not help you with pressure changes with temperature. you need a non-gas for that.

incidently, have anyone taken any tire temps on the stock setup? i will take my pyrometer this weekend and do some spot checks.

james

Claims:
improved fuel mileage
extend tire life
improved handling / performance

Did my tires at costco (free to members) no purchase necessary
do google search on NITROGEN FOR TIRES to find out more.

I felt and heard the difference right away - less road noise / smoother ride

Chances are the reduced road noise and smoother ride came from the new tires, not the gas inside them. Potenza S-02s are notorious for this where they get really noisy as they wear down.

All three claims stem from having a more uniform tire pressure. You can get the same benefit by checking PSI every week.

On one hand the performance gains are not that significant. On the other they are significant enough that people looking for the slightest edge might consider it. Sorta like icing down the headers between autocross runs.

What the Sam Hell you been smokin?

S

I didn't buy new tires from costco - same tires driven on same roads - 4000 miles on them
Have you tried it or is this just a speculative statement?

are you offering smokes? please elaborate beyond a simple statement.

Okay, nitrogen is superior to air in tyres as it has a larger molecular structure. Think of your rubber tyre as a membrane with tiny holes in it. Some of the smaller oxygen molecules escape through it which reduces the tyres pressure. This leads to poor mileage, poor handling, and a lesser tyre life.

The nitrogen molecules, being larger, have a more difficult time negotiating their way through the membrane. Hence, a tyre filled with nitrogen only will maintain it's pressure longer. That's why nitrogen is better. But it is dearer. Buy some good alloy/metal valve caps and stop the loss of air through your valves. Your tyre pressure will be maintained at the correct pressure for longer and you will have all the nitrogen benefits for bugger all cost!

Or, check your tyre pressures weekly with an ACCURATE gauge.....

Regards, Gomez.

In Popular Mechanics this month, Jay Leno talks about some of the special equipment he has in his garage. He uses a nitrogen generator to fill the tires on his fleet.

I have a membership at Costco - do I just go to the garage and ask for nitrogen?

As do I...please do tell.

Since air is approx 80% Nitrogen anyway.....................don't get that it will make a big difference

so many naysayers. i'd like to see more testaments, but after reading some stuff on the net, i don't see any mentions about any performance gains. They only mention benefits of keeping tires inflated properly.

Hmmm, this has me curious. Anyone heard anything about how Nitrogen expands with heat vs. regular old air (ROA?)

What a load of crap!

Improved fuel mileage?
Jay Leno does it?
"I can feel and hear the difference right away."?

......and if the oxygen leaks out, but the nitrogen doesn't, everybody would eventually have (low pressure) nitrogen filled tires, right?
Which also doesn't happen.

Come on people, a tire with 30 psi of air and one with 30 psi of nitrogen would be absolutely the same, and impossible to tell which is which.

Sometimes I despair at the gullibility of the average customer. :(

S

Okay, nitrogen is superior to air in tyres as it has a larger molecular structure. Think of your rubber tyre as a membrane with tiny holes in it. Some of the smaller oxygen molecules escape through it which reduces the tyres pressure.

Um...maybe I didn't pay as much attention in school as I could have, but I'm not sure it works that way. Gas under pressure is gas under pressure, regardless of molecular structure. If you have a tire with 30 psi of oxygen, nitrogen, xenon or whatever in it, then introduce a hole, the tire will leak gas out of the hole at the same rate; this is because gases, by nature, have no volume.

I've had my say....don't believe me? It's a free world, believe what you want! I didn't say nitrogen would not escape, I said a nitrogen filled tyre would maintain it's pressure "longer".

"Lurch, answer the door, the sceptics are knocking!"

Gomez.

What a load of crap!

Improved fuel mileage?
Jay Leno does it?
"I can feel and hear the difference right away."?

......and if the oxygen leaks out, but the nitrogen doesn't, everybody would eventually have (low pressure) nitrogen filled tires, right?
Which also doesn't happen.

Come on people, a tire with 30 psi of air and one with 30 psi of nitrogen would be absolutely the same, and impossible to tell which is which.

Sometimes I despair at the gullibility of the average customer. :(

S

Thank you, finally someone who doesn't just buy whatever is posted on the internet! It is a complete load of crap, indeed. Molecular weight of nitrogen (28) and oxygen (32) is so close, that at 30psig and with the tiny volume of each tire, the weight gains will be so insignificant, I dare anyone to actually calculate them. Especially since 79% of the air you have in your tire right now is already nitrogen. The only benefits would be to reduce corrosion, but this has never been an issue with consumer car wheels. Aircraft tires, shocks, and struts use nitrogen to reduce corrosion, limit the flammability, etc. But not for "performance gains". This is laughable.

EDIT: And to address Gomez's comment....well, I'll just let it go, since I'm not at all interested in starting any flame wars. But let's just say that rubber, by nature, is impermeable, just like polymers, glass, etc. I mean...you can keep 5000psig nitrogen in a *metal* flask without any losses for years. What kind of loss will you have in a couple months from a *rubber* tire? The only volume losses will be due to initial heat of compression - but even then, your tire pressure normally fluctuates with external temperature changes.

-arattle

Look, rubber is not impermeable...rubber is porous. Why do rubber balloons filled with helium deflate quicker than balloons inflated with air? "Cos a helium molecule is smaller than an oxygen or nitrogen molecule, the main two components of air. The helium leaks through the balloon skin at a greater rate due to it's reduced molecular size.

Oxygen which makes up approx 20% of air has a smaller molecular structure that of nitrogen, which makes up approx 80% of air. If you put air in a tyre, then the oxygen component of air will be diffused through the porous tyre carcass at a greater rate than that of nitrogen. Ipso facto, a tyre inflated with pure nitrogen will hold it's pressure longer than the same tyre filled with air.

arattle, nowhere in this thread did anyone mention using nitrogen as a weight saving measure, so I don't know how that came up in your argument! Although nitrogen is lighter than oxygen, for the volumes of gas we are talking about it is worth bugger all, I agree!

Back to the title of this thread though, does nitrogen give you an amazing performance boost? No, but it will allow you to go a little longer between stops to inflate your tyres. Worth it,...... not IMHO. Air is free. As I and PUR NRG said earlier, just check your tyres weekly. Buy some decent valve caps.

Play safe, Gomez.

To all the skeptics: as Gomez suggested in his first post, try Googling for info about nitrogen filled tires. It's fine if you don't believe him (and even I think his claims are exaggerated) but try doing some basic research to back up your arguments.

Nitrogen filled tires does two things:
1. Nitrogen gas leaks out through the rubber slower than normal air. Proven fact but has nominal benefit. Checking your PSI every week would give you almost the same benefit. Properly inflated tires means better gas mileage, reduced wear on tires and better grip.
2. Using a nitrogen fill means the gas going into your tire is dry. This is the key benefit. Ever blast air at a gas station air hose to make sure there's pressure? Notice how sometimes a spray of water mist comes out? If water or water vapor gets into your tire, that water will turn to steam/vapor at higher temps, which increases the PSI in the tire. Overinflating tires is as bad as underinflating.

You can get the same effect by using compressed air (like you fill scuba tanks with) because that air is dry too. Dry air also has the benefit of following Boyle's law and makes estimating/controlling PSI at a given temp easier.

Race teams looking for every edge use nitrogen fill tires. This is not bullshit. This is proven science. If you want to refute then please cite sources to back you up.

COSTCO offers it FREE to it's customers just tell them that you want to refill your tires with nitrogen. For all the people who are just popping off at the mouth without trying it -Attention: THIS IS NOT A SALES PITCH - I DID IT AND FEEL AND HEAR THE DIFFERENCE AND DID SO IMMEDIATELY UPON CHANGING OVER AS DID OTHERS WHO RODE IN MY CAR BEFORE THE CHANGE AND NOW AFTER - THIS IS NOT SPECULATION - YOU CAN'T DISPUTE FACTS THAT ARE VERIFIED BY MORE THAN ONE PERSON WITH NO BIAS. I WAS SKEPTICAL MYSELF UNTIL NOW -2ND DAY OF BEING CONVERTED- do a google search on the matter and find out for yourself - apparently NASCAR knows what they're doing - go argue with them!

There's one reason, and one reason only, why racers use nitrogen - consistent pressure gain with temperature change. Rotamotion and PUR NRG discussed this - since nitrogen is "dry" (ie no water vapour content), the engineers can predict exactly what the tire pressure will be for expected tire temperatures on track. With air, the tire pressure rate of change due to temperature will vary depending on the humidity content. So if you want your tire on track at 220F to be at 32.3 psi, what do you set your cold pressure to? With nitrogen, you can say confidently, 27.6 psi. With air, you say "it depends" - it could be 27.6 with dry air, or 26.2 psi with humid air. That's not good enough for racing purposes!

On the street, however - it makes no difference, and there's absolutely no performance benefit to using nitrogen.

Regards,
Gordon

NRG, it's not my thread....Hollywood Zoom talked about Googling!.

Okay, I have made no statement with regards to the cars ride or the sound produced by tyres filled with nitrogen (although I find it hard to grasp just how that may occur given all that has happened is you have removed the 20% component of oxygen and a little moisture). All I have stated is that there will be no "amazing performance boost" (read, handling/cornering improvement) using nitrogen. The gain is obtained when people who do not check their tyre pressures as often as they should, benefit from nitrogen's ability to maintain the correct pressure for longer. As they say, 35psi is 35psi!

Nascar and other professional race teams use it for the reasons that PUR NRG stated in his post. These reasons are not all that relevant for a road car application. You will not generate the same amount of thermal expansion as a Nascar/F1 racer while you're cruisin' on Hollywood Blvd!

Gomez.

Sorry Gomez for this mistaken attribution.

To reiterate: main benefits of nitrogen fills are reduced gas diffusion and no moisture content. Both benefits are of marginal use for daily drivers. Most likely source of Hollywood Zoom's perceived benefits (noise and ride) come from new tires.

I tend to doubt Costco uses a full purge machine to make sure there's only nitrogen in the tire. More likely they mount the tire (15 PSI ambient air) and pressurize with nitrogen. Going to Costo and asking them to top off tires with nitrogen isn't going to do much.

Here's a challenge for you Hollywood Zoom: go to any gas station, empty the air out of your tires and fill with station air. Repeat once more to make sure most of the nitrogen is flushed out. Then tell me the road noise and handling is significantly different than when you had nitrogen in the tires. I seriously doubt you'll notice any difference.

There's one reason, and one reason only, why racers use nitrogen - consistent pressure gain with temperature change. Rotamotion and PUR NRG discussed this - since nitrogen is "dry" (ie no water vapour content), the engineers can predict exactly what the tire pressure will be for expected tire temperatures on track. With air, the tire pressure rate of change due to temperature will vary depending on the humidity content. So if you want your tire on track at 220F to be at 32.3 psi, what do you set your cold pressure to? With nitrogen, you can say confidently, 27.6 psi. With air, you say "it depends" - it could be 27.6 with dry air, or 26.2 psi with humid air. That's not good enough for racing purposes!

On the street, however - it makes no difference, and there's absolutely no performance benefit to using nitrogen.

Regards,
Gordon I'll second this statement. Main benefits... 100% water free and its stabile at different temperatures. It does not expand and contract like air from an air compressor.

Here's a good link (http://www.trucktires.com/us_eng/library/publications/periodicals/RealAnswers/03v8iss3/ra8.asp)

Pur Nrg - I can appreciate you guys getting all technical and stuff but the KISS principle wins the day. At the cost of being FREE don't knock it till you've tried it - it's a full refill meaning they put the car up on the lift deflate all air from tires then reinflate with nitrogen - I never said anything about topping the air in tires off with NITROGEN.
I don't know about you guys but I have worked in automotive related field for more than 12 years and the smooth ride and handling has always played a part in contributing to overall performance.
You can't beat most bang for the Buck when it's free and someone will even do it for you! It's America Baby, take the free ride for a change - they don't come by too often! ;)

You Rang !!! LMAO :D

Ahh, Cara Mia!

There's one reason, and one reason only, why racers use nitrogen - consistent pressure gain with temperature change. Rotamotion and PUR NRG discussed this - since nitrogen is "dry" (ie no water vapour content), the engineers can predict exactly what the tire pressure will be for expected tire temperatures on track. With air, the tire pressure rate of change due to temperature will vary depending on the humidity content. So if you want your tire on track at 220F to be at 32.3 psi, what do you set your cold pressure to? With nitrogen, you can say confidently, 27.6 psi. With air, you say "it depends" - it could be 27.6 with dry air, or 26.2 psi with humid air. That's not good enough for racing purposes!

On the street, however - it makes no difference, and there's absolutely no performance benefit to using nitrogen.

Regards,
Gordon

I was wondering just how far down this thread I was going to have to read before someone actually cleared this up! I had to get pretty far!

But this is right. Well done Gordon.

Well with all due respect to the critics and scoffers, there may in fact be some benefit in areas where the temperatures get above 100, which means temps on the pavement are 130 degrees plus. The controlled expansion of straight nitrogen just might have some benefits. Where I live the temps get over 100 in the shade; you can imagine what the street surface temps are. For those of us who spend way too much time commuting on freeways, less expansion of air could in fact "improve" the ride because the tire pressures don't increase as much. This might make it a bit quieter too.

If in fact Costco does this for free, I'm going to go down and check it out. Certainly can't hurt. I'll let the forum know if they do or not, and if so, what effects if any it actually has.

I could have swore tires was spelled with an "i" not a "y". Thats all I have.

I could have swore tires was spelled with an "i" not a "y". Thats all I have.

Thanks for your input Mr Speelcheckar!
Proper english grammar would have dictated the use of the word, "sworn". ;)

Your Webster's dictionary would spell the word "tyre", tire. I venture to say most other parts of the english speaking world would spell the word the way I spell it. Actually, the foot thick (30cm!) circa 1960 Webster's I have here has both spellings!

Gomez.

hey i have that dictionary!!

Learn to take a joke mate!

That's one good looking dictionary by the way.

Learn to take a joke mate!

No Wukkers!

Hollywood Zoom- YOU'VE GOT TO BE KIDDING ME!!. You remind me of this guy named Brandon I used to know. Brandon ran his mustang into a phone pole and it crunched up the hood in the front making another opening above the grill. His car stayed that way for months and finally I asked when he was going to get it fixed. He said he was going to leave it that way because now it had ram-air and it was noticably faster. Maybe he had nitrogen tires too! And a supercharged paint job, and a nitrous filled steering wheel, and flamethrower spark plugs.

I fill my tires with NOS. Excuse me...

NaWs y0.

But seriously, I'm a lazy a-hole, I may just try the nitrogen thing at Costco next time I go.

the reason why Leno uses it, is because he has a fleet of cars and doesn't have to fill the tires up everytime he want to take one out for a ride.

Gee anyone knows that who stores there car. My last sports got 9000 mile on it in 2 years.

The Rx8 sits in the garage all the time too. Cement gets cold and dfaltes the tires all the time. I have to refill my tires all the time bercause it is in storage.

Not something you want to do when your rich and you just want to pop into a vehicle and go for a spin.

Ummm which of my 4 vehicles do I want to drive today?

I know that racecars use it but nitrogen is a lot cheaper nowadays and should be availiable at some gas stations soon.

When I had my AD07's installed with Volk LE37's the dealer topped up with N2....perfect. Haven't needed to go back for another top up yet, but will do when the time calls :)

with my miata i would get the cars alignment and ride hight dialed in and get the car corner weighted at a shop. he would alwasy highspeed balance the tires and fill them with nitrogen. he also let me sit in the car when we adjusted everything, a lot of shops wont let you sit in the car on the lift....

the question : is it really worth it? on a street car.....no not really (IMO) but if you track the car a lot, or its a race only car, sure why not.

I purchased new tires from Costco recently (for my truck) and they now only use Nitrogen to fill them.

Not sure where to go if I need to top off the tires a bit but nice to see that Costco has made the switch.

Simply filling/topping off the tire with nitrogen is a half-assed job since there is still some moisture in the ambient air inside the tire to begin with. (If you assume 15 PSI ambient, a 30 PSI fill means you still have half the moisture to contend with.) You really need to flush the tire air to get the full benefit of a nitrogen fill.
________
LOVE QUOTES FORUM (http://www.love-help.org/love-quotes/)

:rolleyes: so your tire gauge reads 15 PSI all the time???

I use a special nitrogen blend in my tires. 80% N ....O2, bit of He, H, Arg, water vapor make up the rest :D

lol, Danno beat me to it. Nitrogen is mostly just a gimmick. Come on, Tire Disounters uses it as their big marketing ploy, even puts lime green stem caps on so they look cool too.

Guys, nitrogen is not a gimmick but the reason you use it is easily misunderstood. It isn't the nitrogen gas itself--it's the lack of any moisture in that gas. You could use compressed air to achieve the same effect--provided that air was completely dry. Most air compressors accumulate water in the tank which then gets into the tire. When the tire heats up the water turns to vapor and expands dramatically--with a corresponding spike in tire pressure. Eliminate that moisture and you eliminate fluctuating tire pressures.
________
Lancia Lc2 (http://www.ferrari-wiki.com/wiki/Lancia_LC2)

I have a compressor that puts out totally dry air from another hobby...I purge the tires and refill ...no water vapour problems :D Any guesses on the hobby :D

Wild guess, scuba diving?

It's good for people that store their cars. their tires don't go flat as often.

No benefit for the average driver.

Wild guess, scuba diving?
Good guess......water vapor really sucks when you are ice diving in the winter :D

I use a special mix of gasses:

78% Nitrogen
21% Oxygen
1% Water
Trace amounts of Ar CO2 HE CH4 Ne

Oh, and a teeny tiny touch of O3

:D

Good guess......water vapor really sucks when you are ice diving in the winter :D

Actually, it doesn't suck, that's the problem! :rolleyes:

Well..actually the regs usually freeze open and free flow....you need to suck as much as you can and hightale it to the hole :D

Guys, nitrogen is not a gimmick but the reason you use it is easily misunderstood. It isn't the nitrogen gas itself--it's the lack of any moisture in that gas. You could use compressed air to achieve the same effect--provided that air was completely dry. Most air compressors accumulate water in the tank which then gets into the tire. When the tire heats up the water turns to vapor and expands dramatically--with a corresponding spike in tire pressure. Eliminate that moisture and you eliminate fluctuating tire pressures.
I simply thought the use of nitrogen in tyres was a safety thing. Less danger in the case of a brake fire. We use them all the time in aircraft tyres for that reason. Good explination (above) was really confused before your explination what the benefits on a streetcar would be. Got an unlimited supply of nitrogen at work, but dont think i will bother using them in my tyres. Wayyyyy too much hassle. I'll stick to dry air outta my compressor at home :)

Sorry if this is a repost but I read that nitrogen in tires give the car better performance. Is this true? If it is, how many of RX8er here do it?

My brother drives a G35 coupe and he regularly visits this site and so I stumbled upon this article (http://g350z.com/showthread.php?t=145).

"Many race car teams use nitrogen instead of air in their tires because nitrogen has a much more consistent rate of expansion and contraction compared to the usual air. Often, a half pound of pressure will radically affect traction and handling. With track and tire temperatures varying over the duration of a race, the consistency of nitrogen is needed.

Nitrogen pressure is more consistent than normal air pressure, because air typically contains varying amounts of moisture due to changes in the relative humidity on race day. Water causes air to be inconsistent in its rate of expansion and contraction. So, a humid race in the southeast United States or a dry race in the desert western United States could make for unpredictable tire pressures if "dry" nitrogen were not used. Nitrogen is also used in the high-pressure tires on large and small aircraft. "

other info http://www.popularmechanics.com/auto...tml?page=2&c=y

http://www.techcentralstation.com/111604D.html

http://www.tirelast.com/id5.html"

It was pretty interesting. Check out these Enkei (http://enkei.com/RacingSeriesSpecs/GTC%2001.html) wheels that let's you insert nitrogen while bleeding out air. Dual valves! Sick!

if the wheel has dual valves good idea. if you are at the 95% of driving skill.. or just for fun... if you have one valve you are getting it in the, well..

not a good idea..

beers :beer:

nitrogen will stay in the tire longer.
when there are temp changes from cold to hot, tires with air will loose pressure

tires with nitrogen will keep a steady psi no matter what

i know at least one bmw dealer out here has installed nitrogen "pumps" for their service center they sent out a flyer advertising the benefits of using nitrogen and that they had one installed.

w/air you're also adding water vapor in the tire. which when it condenses the small amount of water stays in the tire. saw it on Goss' Garage on MotorTrend (PBS)

it's simply a marketing gimmick to separate $$$ from uninformed motorists, you're not driving an Indy car :hahano: it's of no consequence for the pressure to fluctuate on the typical street car tire

the atmosphere is already 75% nitrogen, the difference between oxygen and nitrogen is small and only a small portion of the remaining air composition, and most leaks are not osmonic in nature, not to mention that you should be checking your pressure on a regular basis anyways because you can't foresee small cuts, picking up a nail, etc. ....

it's simply a marketing gimmick to separate $$$ from uninformed motorists, you're not driving an Indy car :hahano: it's of no consequence for the pressure to fluctuate on the typical street car tire

the atmosphere is already 75% nitrogen, the difference between oxygen and nitrogen is small and only a small portion of the remaining air composition, and most leaks are not osmonic in nature, not to mention that you should be checking your pressure on a regular basis anyways because you can't foresee small cuts, picking up a nail, etc. ....

Agreed.

and of course there's not an N2 tank on every corner when you do need to add pressure, and you will need to ...

When I got my new tires installed and balanced they filled with nitrogen. No charge. Good
The Chrysler dealer wanted $60 for nitrogen fill! Bad...

Any difference with nitrogen? Not that I've noticed.

tires with nitrogen will keep a steady psi no matter what

Somebody hasn't learned about the gas laws (http://en.wikipedia.org/wiki/Gas_laws).

Short story, any gas that changes temperature in a fixed volume will change pressure. The type of gas really only affects the degree to which a change in pressure, volume or amount of gas affects the rest of the equation (calulations are usually adjusted by Van der Waals constants (http://en.wikipedia.org/wiki/Van_der_Waals_constants_%28data_page%29)).

Nitrogen makes NO difference on a street car. It's actually worse because you're paying for it and regular air is basically free. The only potential value I see is if you're storing tires long term and trying to prevent dry rot.

The only reason racers use it is that it's much easier to exactly calculate the change in pressure due to change in temperature. You can still be pretty close with regular air, just not as exact because of humidity changes, elevation changes, etc.

Unless you are skilled enough to be at the top tier of professional racing and are driving a race car where there are major changes in tire temperature it's dumb to fill your street cars tires with nitrogen.

When I got my new tires installed and balanced they filled with nitrogen. No charge. Good
The Chrysler dealer wanted $60 for nitrogen fill! Bad...

Any difference with nitrogen? Not that I've noticed.


You paid for it whether you realized it or not ...

Does any have any input on this? The local dealer says it increases tire life around %35 if I remember right and gas mileage 1 or 2 mpg. I've been looking around and seem to get mixed reviews. What happens if your tire pressure is low? Do I have to get to the dealer again and pay another $25 to correct the pressure? Say if you were on a road trip and needed air can you add air to the nitrogen or would I have to go to a supplier?
What about fix a flat, can you still use it? Not that I would unless I was stranded but it could happen.
Anyway any thoughts or ideas would be helpful.

Btw new to the board. Just pick up my 04 rx8 last week. So far I love it! Miss the turbo my FD had but that can be taken care of :evil_laug

O one more this had the emmisions recall done and there saying there was a misfire code and I need new plugs and wires. If I read right shouldn't they have replaced the plugs when doing the recall?

well a little back ground first... Nitrogen is the new sales tool in tires.

78.08% of all air (at 1000ft above sea level) is Nitrogen, so bumping it up to 98% (the average when a tire is filled) is not a big jump as basic air is mostly Nitrogen.

The idea, is that pure nitrogen leaks less through the rubber of the tire, so tires stay inflated to the set pressure much longer. Also since most tires are filled either by a tank or Nitrogen generator (or more accurately a scrubber) there is the potential for less moisture to be placed into the tire, in combination with less Oxygen, means reduced possibility of internal degradation of the tire and rubber.

So if less air leaks from the tire, and tires stay at set pressure longer, that is where they are claiming increased tire life and increased mileage. If you stay on top and check your tire pressure regularly then using nitrogen will really make no difference.

As far as adding tire life from lack of Oxygen. Since you generally are using performance tires on a RX-8, the tire life is usually less than 5 years anyway. If you are long term storing the car, then the extra life of nitrogen will help.

You can top off nitrogen filled tires with regular air, since again, regular air is mostly nitrogen anyway.

And if they are charging you $25 for nitrogen in the tires, they are ripping you off.

When they fill a tire with nitrogen, do they first evacuate the air so there won't be any oxygen or water vapor in it?

Racers use nitrogen rather than air because it's dry, and the absence of water vapor makes the tires behave more consistently. IMHO, racers began using nitrogen instead of air because they needed a compressed gas supply in the pits and bottles of nitrogen were easier to come by. I'll buy into the "no moisture" bit because water vapor is not as well behaved as nitrogen or oxygen, and racers need to push every detail they can.

Selling consumers on nitrogen instead of air is, in my opinion, bull. Air does not really diffuse out of tires. Unless there's a leak, the only change I've ever seen in tire pressure is from seasonal temperature. It won't make tires last longer, since the outside is still exposed to air. And the precision that racers crave is just not relevant on the street.

Nitrogen in tires is right up there with restaurants selling bottled water instead of giving tap.

Ken

do a quick search. all of your questions have been answered before.

The reasoning behind using Nitrogen, is not to save the tire but to save the rims.
nitrogen is an inert gas, as air contains moisture and corrosive particles. Remember Rubber doesn't break down and corrode until about your 10,000 year mark. Why tires go bald is do to wear and tear of driving. Now granted that the sun can do lots of harm to your tire, but that is the outside of the tire. As Nitrogen or air are on the inside. If you ever looked at an old car, say at a junk yard. You will notice that the outter tire is cracked and partly brittle, but if you remove the tire the inside is like new.

So in short Nitrogen is meant to reduce the corossive element to your rims and valve stem, not to preserve your rubber.

I've heard a bit of everything in each of the posts, but none of all.

I've heard that the idea behind it is that there is no moisture in nitrogen (n2) as there is in oxygen (o2). this means that heat will not affect the pressure of the tire.

additionally i've heard that the n2 molecule is larger than the o2 molecule and so the dispertion rate through the rubber is slower, and it will stay inflated longer compared to o2. (this is disuputed by wikipedia.org)

lastly the third benefit i've read about is that nitrogen won't oxidize the inside of your tires as oxygen will. if you read blackbelt's post (which i agree with) this seems like a bs reason to buy nitrogen.

nitrogen fills are about $10 a tire, if you consider the 3% (alleged) increase in mpg, the cost effectiveness of this doesn't really add up.

my .02

I just bought some s-03 and was wondering where to get them installed and walmart does it for $4.00/ tire plus someother things comes to about $44.00 total but not nitrogen. Glad I read this, Walmart here I come.:)

Had my tires replaced about two weeks ago and had them filled them with nitrogen... I would have never thought that it would make a difference, but I burned through 3 tanks of gas in the last two weeks that were all highway miles and did notice some change. Over the last 6 months I have averaged 23.8 miles per gallon when I burn the entire tank on the highway only stopping for gas.. I got 25.1 and 25 out of my last two tanks and 25.3 out of the tank I burned through today.. I still think it is a fluke and probably had more to do with air density and humidty for optimal engine operation than the nitrogen

Nitrogen in the tires will not give the car better performance. Nitrogen is larger than oxygen. Hence keeping the psi steady and if you happen to need to had air to your nitrogen filled tires you can add oxygen" regular air"

The advantage of using nitrogen imo is that it is drier than air and will not corrode the TPMS sensors as quickly.

unless you're racing IndyCars or Formula1 it's basically bullsh-t marketing on a street car

a) To do it properly you either need to pull a vacuum on the tire to evacuate out all the moisture and dirty air before inserting the N2 or you need two valves to continously purge N2 in and out of the tire for some length of time to accomplish the same

b) What are you going to do if you have a low tire and there's no N2 source around, which is an extremely likely scenario. Well obviously you're going to dump in dirty/moist air, which suddenly shoots this overly anal theory in the foot.

If i could get nitrogen in my tires i would but i am no going to pay the price they want to put nitrogen in. I will stick with checking my tire pressure every 3 weeks. For every 10 degrees colder you lose 1 pound of pressure in your tires. The only advantage nitrogen has over air is keeping your pressure stable so you dont lose gas mileage due to low tire pressures

I still see my tires pressurize the same amount at the track using N2 so I agree with you Team RX8 that it is hard to get moisture out of the tire once it is in. BTW I have a nitrogen bottle in my garage and I have an air tank that I fill up for use at the track. When I raced I would use the N2 bottle to run air tools. Very handy

Argon for the win :)

so when I eventually need to fill up my tires, it's ok for me to put regular air into the nitrogen filled tires?

you need two valves to continously purge N2 in and out of the tire for some length of time to accomplish the same

think about it. not sailing against the wind here..


beers :beer:

Some places like Big O Tires charge $5 for the life of the wheel/tire. If ever you need to add pressure and there's no Nitrogen available, you can add air temporarily and you can come back to them and have them purge the air out and refill with Nitrogen. This migh not make sense if you have a wheel with single valve stems since you can't completely purge the air out but if you have 2 valve stems on your wheels like my NT03 +M, you can fill it up with nitrogen and evacuate the remaining air in the tire simultaneously.

nitrogen will stay in the tire longer.
when there are temp changes from cold to hot, tires with air will loose pressure

tires with nitrogen will keep a steady psi no matter what

Umm... no. Go back and reread your high school physics book.

Nitrogen is a gas. Just like any other gas it expands when heated and contracts when cooled. In a tire this means that as the tire heats up from rolling friction the pressure in the tire increases. This happens whether your tire is filled with air, nitrogen, hydrogen, helium, or whatever.

The benefit to nitrogen is that it is a dry gas (i.e., has zero moisture content). Therefore, the rate of expansion can be easily calculated. It is harder to calculate the expansion rate with air, because you must factor in the moisture content, which is constantly changing. Many race teams use nitrogen so that they can accurately predict tire pressures for a given temperature.

On a street car that never sees track time, nitrogen is worthless. You won't see any performance benefit (your tire pressure will still decrease when it gets cold, just like air), and you'll need to pay someone every time you need to adjust your tire pressure, unless you happen to have a tank of compressed nitrogen in your garage. Don't waste your money.

Had my tires replaced about two weeks ago and had them filled them with nitrogen... I would have never thought that it would make a difference, but I burned through 3 tanks of gas in the last two weeks that were all highway miles and did notice some change. Over the last 6 months I have averaged 23.8 miles per gallon when I burn the entire tank on the highway only stopping for gas.. I got 25.1 and 25 out of my last two tanks and 25.3 out of the tank I burned through today.. I still think it is a fluke and probably had more to do with air density and humidty for optimal engine operation than the nitrogen

you're probably experiencing this as what others have stated: nitrogen is more stable than air, etc.

most autoxers know how fast temps and pressure changes on even one quick run. so you're just experiencing the higher psi gains that trickles down to your mpg gains.

whereas most streetcars filled with air should measure and add air "cold" for an accurate reading. nitrogen cuts that out.

like so many others stated with good analogy, its maybe only good to use for storing tires, and if you're an racer where consistent cold/hot temps and tire pressure makes a difference for you.

like stated above just a marketing gimmick for the mass media of the uninformed

whereas most streetcars filled with air should measure and add air "cold" for an accurate reading. nitrogen cuts that out.


Nitrogen is a gas. It is still subject to PV=nRT

Therefore, your cold pressure readings are still going to be significantly different than your hot temperature readings.

Nitrogen is larger than oxygen.

since when?!??! nitrogen is element number 7 and weighs 14 grams per mole, oxygen is atomic number 8 and weighs 16 grams per mole. Both nitrogen and oxygen form diatomic gaseous molecules in steady state. Guys seriously a little bit of basic chemistry knowledge would help the lot of you.

I like helium. It reduces your unsprung weight.:)

LOL at Helium!!!!! Honestly I work for a Toyota Dealer and its a customer preference, similar to conventional and synthetic oil but I know a few technicians who have used the Nitro Fill (Nitrogen Filler) and didn't have a significant effect. One technician stated that it made it relevant that his tires needed to be replaced because they leaked more lol, but I don't honestly know what to say. Its a personal preference in which you would like to use. I'd personally use whats free till that costs something (damn economy). :icon_tdow

since when?!??! nitrogen is element number 7 and weighs 14 grams per mole, oxygen is atomic number 8 and weighs 16 grams per mole. Both nitrogen and oxygen form diatomic gaseous molecules in steady state. Guys seriously a little bit of basic chemistry knowledge would help the lot of you.

you beat me to it :(

the reason nitrogen is used in airplane and racing tires is due to the uniformity of the molecules in the gas. You could use any pure gaseous molecule to get the same advantage, you could use 100% CO2, you could use 100% O2, hell you could use a real complicated gas like bromochlorodifluoromethane (halon). At the end of the day pressure is pressure is pressure, thats the nice thing about gas, it obeys a set of rules (for the most part, using halon probably has a large van der waals effect), nitrogen is used because it is cheap and easy to purify, but isn't an accelerant like the other cheap and easy to purify gas is.

Any views on it? I have never used it but was having a conversation with my mechanic about it a few months back, and when he put my tires on he told me he filled them up with nitrogen for free. Anyone else use it? does it really matter? i mean if its free why complain. but is it really worth ten bucks a tire for everyone else? i cant tell since i just got my new tires, already it feels like a whole new car again. lol.

just dont get your tires TOO hot, they might explode! before you know, your 10 feet in the air about to come down on some stupid honda....:rofl:

well since the tires are new. im making it a point not to do any doughnuts or burnouts, very difficult to resist the urge, but i need them to last longer than 4 months this time.

well since the tires are new. im making it a point not to do any doughnuts or burnouts, very difficult to resist the urge, but i need them to last longer than 4 months this time.

4 Months?!?

I just got new tires, $800. Ha I would be pissed if I had to get a new set after 4 months.

i mean... completely my fault...so i can only be so mad..lol.

i just messing with you, i heard nitrogen is better than air...dont know

yeah that's what i heard but i figured it was just b/s to make money.

atmosphere is 80 percent nitrogen. 20 percent more can't hurt, but i don't know how beneficial that would be.

It's lighter.

derr... i just read up.

unless you drive f1, it's not gonna make a difference (marketing ploy):)

yeah i figured. but it was free. so why not right.

More stable pressure under weather condition ie:take off here in Winnipeg during the winter -20-35C and land in Florida +15C the tire will remain virtually at the same pressure and pretty much free of water (the reason for being more temp. stable).....Nitrogen is used in most Aircraft tires...for that reason alone....

More stable pressure under weather condition ie:take off here in Winnipeg during the winter -20-35C and land in Florida +15C the tire will remain virtually at the same pressure and pretty much free of water (how it's more temp stable).....that is what it's used in most Aircraft tires...for that reason alone....

+1...

Pretty much b.a. to use in cars.... dont have to worry about them going low too often as the molecules are much larger than that of oxygen..... so therefor it leaks less

More stable pressure under weather condition ie:take off here in Winnipeg during the winter -20-35C and land in Florida +15C the tire will remain virtually at the same pressure and pretty much free of water (the reason for being more temp. stable).....Nitrogen is used in most Aircraft tires...for that reason alone....

and only done properly if the wheel has two valve stems..

beers :beer:

and only done properly if the wheel has two valve stems..

beers :beer:

No! :spank: :lol:

The big benefit of nitrogen is not really the nitrogen, as was pointed out air is ~80% nitrogen, its the lack of water. Compressed nitrogen has also been dehumidified. Its the moisture in un-dried air that a standard compressor packs into the tire that causes the problem as it causes a greater range of pressure increase with increasing temperature than dry air or dry nitrogen causes. So the only real advantage of using nitrogen is less pressure change with temperature which can be an advantage at the track but is really not much of an issue on the street. You can also achieve most of the benefit by using dehumidified air (like from a dive shop) which I am thinking about doing as I have a scuba tank in my garage.

Nitrox?
like swoop said you can't remove the moisture from the tire with one valve stem.
the rx8 pressuer sensors do not like moisture

Nitrox?

Well that would have even less nitrogen in it than air as Nitrox is higher oxygen cotent than air and its more expensive. I'm gonna go with plan old dehumidified air.:cool:

the problem the way I see it is that the air compressors that are used by the tire companies
do not have automatic drains and the water tends to build up. Air Force bases have a strict proceedure of signing off on manually draining the compressors every morning.
I know about Nitrox I am certified to dive with it

Its not just the draining of accumulated water in the compressor, unless the compressed air is passed through a drier you are concentrating the humidity present in the air (which is significant here in Florida) when you compress it even though it is still in the vapor state and not precipitated out as a liquid. Draining the compressor tank and lines merely removes the extra water that has precipitated out in the tank and lines. While this is a good idea, the compressed air within the tank still has a high humiditiy (higher than ambient since you compressed it) until you do something to remove it from the vapor (gaseous) state like passing it through a drier. It is this vaporized water that is the problem that dry air and nitrogen fills attempts to alleviate.

I filled my tires with helium and attached a GT wing. Now I can fly.

I filled my tires with helium and attached a GT wing. Now I can fly.

Yes but now your RX8 has a tendency to flip upside down and fly upside down. You will lose all of your fluids, this is a terrible idea.:lol::Eyecrazy: Didn't yo mama never tell you not to put water wings on yo feet boy.

I never listen to her, I was water skiing under my own power at the age of 5, biatch.

My tire dealer recently got outfitted to inflate tires with Nitrogen. For $39, they will re-inflate all 4 tires with Nitrogen and, for the life of the tires, if you ever need your pressure adjusted, or if you have a flat and get it repaired, they will refill with Nitrogen. If you have to adjust the pressure with regular air or have a flat fixed elsewhere, I can take it back to them to have it refilled with pure Nitrogen at no extra charge.

There were a couple of selling points for the Nitrogen. One is that the pressure is supposed to remain more constant and is not as sensitive to outside temp changes. The other was that it is supposed to improve the ride and soften it somewhat.

It is also not as susceptible to moisture buildup which can damage the tire pressure sensors inside the wheels. They told me they are now starting to see some early 2000+ models come in with tire pressure sensors damaged by moisture over time and needing to be replaced - and they aren't cheap.

I recently put a set of Michelin tires on my wife's Jeep that are typically good for 70 or 80 thousand miles so I thought it might be worth it to invest in the Nitrogen. There did seem to be a noticeable difference in the ride. Her Jeep has a tire pressure monitoring system and reports the pressure and alerts for each wheel individually. It's a pain in the winter when tire pressures go down so I'll be interested to see how different it is with the Nitrogen.

It seems like the type of tires that can be had to fit the 18" rims on the '8 (low profile performance tires) don't really lend themselves to an extended amount of mileage. So, I'm wondering if it is worth it to go with the Nitrogen. Curious if anyone else has done it and do you notice any significant difference? Right now, I have Kumho ECSTA-something or other tires on my '8 and they have about 16k on them. Tread still looks good but I've been told not to be fooled, they may wear out in another 10 - 15k.

I run 78% nitrogen and 21% oxygen, with a small amount of some trace gases, in my tires. ;)

Complete waste of money, unless your rx8 is a certified airplane you'll never see the temperature change they describe.

I run 78% nitrogen and 21% oxygen, with a small amount of some trace gases, in my tires. ;)

:lol: +1

I run 78% nitrogen and 21% oxygen, with a small amount of some trace gases, in my tires. ;)

Damn, that must be so volatile at normal running temps :(

I put helium in mine, makes them lighter. Nitrogen is for suckers!

I've heard of it but after looking into it, it just did not seem that the pro's were enough to just-tee-fi it to me.
Never heard or read about a better ride however....

Plus after years of using "regular" air I just didn't/don't see a need.

But if it works for you, go for it.

well i asked about it awhile ago while at the shop. and they gave me the same speech. so when i got the new tires put on they told me that they went ahead and filled the tires with nitrogen (no charge) and honestly i dont see any down side. not sure if i can say i see a upside though. since they were brand new tires, i cant say that any difference i experienced was due to the nitrogen.

the only way your running all nitrogen if if they pull a vacuum on the tires before filling.... and i prmise you they didn't since thats impossible to do

I run 78% nitrogen and 21% oxygen, with a small amount of some trace gases, in my tires. ;)

Damn, you beat me to it :)

I run 78% nitrogen and 21% oxygen, with a small amount of some trace gases, in my tires. ;)

I don't care who you are - that's funny right there. :lol:

As far as "vacuuming" out the "air", I don't know how tightly they do it but part of the process is sucking the air out before filling it with Nitrogen. And I don't mean just letting the air out, it is sucked out.

The main thing that sold me on trying it was the sensitivity, or lack thereof, to temperature change as far as pressure goes. I don't know about other racing series, but I know that reason is exactly why NASCAR tires are inflated with Nitrogen - to control how much pressure builds up from the heat. So, there has to be some science to it. How much transfers to a car with street tires at highway speeds, I don't know.

I know that, in the winter time, the tire pressure monitoring system drives my wife nuts with low pressure alerts which means she, in turn, drives me nuts to fix it all the time. I had this done about 6 weeks ago so it hasn't been cold enough to see if this will be a cure for it. We shall see.

Maybe I just paid $39 for the tricked out little green valve stem caps they put on to indicate they are filled with nitrogen. :)

Well, short of protecting the TPMS sensor, I don't think normal daily driving would really demand for it.

Unless you roll in the GT-R round that 'Ring =p

Tire pressures are supposed to be checked when the tires are cold.

If the nitrogen dealer is going to adjust tire pressures, what are the logistics? Do you leave the car overnight? Do they give/sell you a good tire gauge so you can check pressures at home when they're cold, record the numbers, then let them add a difference after you drive over?

It's my belief that race teams started filling tires with nitrogen for the same reason they use nitrogen for the air guns on pit lane.

Ken

Nitrogen beneficial for racing. For a DD, waste of money. In the cold when tire deflates a lb or two, or dear god no! Add it back in at the gas station.

Tire pressures are supposed to be checked when the tires are cold.

If the nitrogen dealer is going to adjust tire pressures, what are the logistics? Do you leave the car overnight? Do they give/sell you a good tire gauge so you can check pressures at home when they're cold, record the numbers, then let them add a difference after you drive over?

It's my belief that race teams started filling tires with nitrogen for the same reason they use nitrogen for the air guns on pit lane.

Ken

No, I wouldn't and I don't think they expect you to bring the car to them and leave it if your monitor says it's low. What I'm saying is that if you use a regular air hose to bring your tires up to pressure, the cost covers you taking the car back to them to have them refilled with Nitrogen to the proper pressure. I hear you that they should still be cold when doing so. But, the point is or is supposed to be that you shouldn't need it done to begin with because of the Nitrogen. However, if you get a flat and have to have it repaired and filled with regular air, the cost covers taking the repaired tire back to them to be refilled with Nitrogen.

Race teams use Nitrogen for impact wrenches because they more reliable and can make the guns spin faster. They use it in the tires to better control the amount of pressure buildup once the car hits the track and starts to buildup heat in the tires.

Tire pressure varies with ambient temperature, so you have to add or subtract air (or nitrogen) at least seasonally. Also add some periodically to replace what hisses out when you put a pressure gauge on the valve. I't not just if something goes wrong. I bought a small compressor because pumping tires myself in my garage is less trouble than keeping track and having to calculate the delta to add to warm tires after driving to a gas station.

I've always thought that race teams use nitrogen because it's available, doesn't cost a whole lot, and a bottle of gas is more reliable than a compressor. At home, though, I'd rather not have a high pressure gas bottle sitting around.

Ken

Air Pressure: When and How to Set (http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=147)

The cynics here are correct. Being a science junky of sorts, I researched the chemistry and physics involved in the claims. Basically, they won't get sued for what they're selling, but other than that, it's all a bunch of bullshit.

The only benefit was to drive up the stock price for industrial nitrogen supplier companies. They appreciate your business!

at least you get a phenomenal set of four lime green valve stem caps, holla fo' a baller ....

Rolled five N2 threads into one, so the airheads can find it easily, and stop making new ones....

S

What is Nitrogen Inflation and is it beneficial? (http://www.centraltireva.com/faq/printable.php?p=default&cat=5#a35) See #6