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Apr 12, 2007 1:23:55 PM
- 69bossnine
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Re: Anybody tried nitrogen on their tires?
I've looked into this, as I've got a large collection of cars with my father that do alot of "sitting", and was attracted by the CLAIMS of reduced leak-down rates and reduced internal corrosion... What I found out was that the consensus of those "in the know" find it to be a crapload of hoopla, another good way that your local Midas can make some extra dough... Anecdotally...Both Michelin and Goodyear are fairly non-commental on this issue. Neither of them recommends nitrogen in their tires...but they are sort of skirting the issue, likely so as not to [beep] off the big tires stores that are pushing this stuff.
Let me see if I can find a good decent seemingly unbiased rant on it...
Here ya go..
pisgahchemist (Chemical) 20 Jun 05 16:39
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.
Let me see if I can find a good decent seemingly unbiased rant on it...
Here ya go..
pisgahchemist (Chemical) 20 Jun 05 16:39
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.
Apr 12, 2007 3:12:19 PM
- MMD
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Re: Anybody tried nitrogen on their tires?
I loooove the way they say using nitrogen "improves gas mileage."
What they are really saying is nitrogen-filled tires lose pressure more slowly than air-filled tires.
So dummies who never check their air pressure WILL have _slightly_ better mileage with N-filled tires.
Like 69bossnine is saying: N-filled tires start to make sense in specialized applications like maybe the space shuttle or F-16s.
What they are really saying is nitrogen-filled tires lose pressure more slowly than air-filled tires.
So dummies who never check their air pressure WILL have _slightly_ better mileage with N-filled tires.
Like 69bossnine is saying: N-filled tires start to make sense in specialized applications like maybe the space shuttle or F-16s.
Re: Anybody tried nitrogen on their tires?
Quote:
Dan L said:
This subject is pretty silly. I service my tires with 78% Nitrogen. I like that mix.
There will always be some market guru looking to make a buck off this whole thing.
dan
LOL.
I would do it in my wife's car since she never checks the pressures and they'd stay filled longer (would save me some time). BUT who's going to drive the sukker to get the tires topped up with N?
Sounds like a great idea (for specialized situations including the space shuttle and a lazy wife) but all that hope and resolve fades after you sign the contract and first buy the N-filled tires.
So, it's a GREAT marketing plan/gimmick.
Re: Anybody tried nitrogen on their tires?
Quote:
1st997 said:
I ONLY use Helium so my wheels are lighter....
(This was to be posted 4/1)
hahaha. The TV show Mythbusters tried the Helium-filled football field goal thing. They were quite scientific and found it has no effect. That show ruined the whole question for me.
Re: Anybody tried nitrogen on their tires?
glad i went the tank route last year...over the course of winter the 2 cars tires i filled lost zero pressure...but best of all i will never, repeat never, have to make the trek to a gas station / convenience store / scumbag hangout for air only to discover that someone has "inadvertently" trashed the entire setup and store management has neglected to get it fixed
Apr 16, 2007 3:18:53 PM
- 69bossnine
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- Reply to: SrfCity
Re: Anybody tried nitrogen on their tires?
Quote:
SrfCity said:
FWIW, all the Michelin tires at the ALMS race in Long Beach were nitrogen filled. I suspect that it results in less pressure fluctuation.
The above info I posted plainly debunks the pressure-fluctuation theory. Are you sure that "Tuffy Auto Service Centers" doesn't have a sponsorship-deal with the Long Beach ALMS??
Apr 16, 2007 3:23:21 PM
- 69bossnine
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- Reply to: roadtrip
Re: Anybody tried nitrogen on their tires?
Quote:
roadtrip said:
glad i went the tank route last year...over the course of winter the 2 cars tires i filled lost zero pressure...but best of all i will never, repeat never, have to make the trek to a gas station / convenience store / scumbag hangout for air only to discover that someone has "inadvertently" trashed the entire setup and store management has neglected to get it fixed
Air compressors are very cheap at Walmart... makes a hell of alot more sense than scouting convenience stores for 75-cent air..
I parked my '97 Saleen for well over a year without moving it once, with NO pressure-loss. Just regular-ole-air in the tires. Don't knee-jerk-attribute lack of leak-down to the Nitrogen, attribute it to the good bead seal between your Michelins and your quality wheels, and quality valve-stems. My Saleen runs Pilots on Speedline Magnesiums.
Apr 16, 2007 4:19:27 PM
- MMD
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Re: Anybody tried nitrogen on their tires?
You gaaaaahtta have an air compressor. 
There's uses around the house and garage which you've never dreamed of.
There's also that other thing of tires having an innermost layer which is there specifically to prevent air from seeping out. Rubber is porous and so needs this coating. There's no telling (without tedious internet research) if high-quality tire mfgrs have by now started using a compound which completely eliminates air seepage. 69Bossnine's Saleen with zero pressure loss is a clue. This would make the most common advantage offered by N-filled tires redundant.
There's uses around the house and garage which you've never dreamed of.There's also that other thing of tires having an innermost layer which is there specifically to prevent air from seeping out. Rubber is porous and so needs this coating. There's no telling (without tedious internet research) if high-quality tire mfgrs have by now started using a compound which completely eliminates air seepage.
69Bossnine's Saleen with zero pressure loss is a clue. This would make the most common advantage offered by N-filled tires redundant.
Apr 16, 2007 5:49:47 PM
- SrfCity
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- Loc: Orange County, CA
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Re: Anybody tried nitrogen on their tires?
Quote:
69bossnine said:Quote:
SrfCity said:
FWIW, all the Michelin tires at the ALMS race in Long Beach were nitrogen filled. I suspect that it results in less pressure fluctuation.
The above info I posted plainly debunks the pressure-fluctuation theory. Are you sure that "Tuffy Auto Service Centers" doesn't have a sponsorship-deal with the Long Beach ALMS??
No, but Airgas does
Re: Anybody tried nitrogen on their tires?
Quote:
roadtrip said:
glad i went the tank route last year...over the course of winter the 2 cars tires i filled lost zero pressure...but best of all i will never, repeat never, have to make the trek to a gas station / convenience store / scumbag hangout for air only to discover that someone has "inadvertently" trashed the entire setup and store management has neglected to get it fixed
If Nitrogen works I'd consider it 100%. My tires always seem to need adjustments. Last straw for me was trips to 3 different gas stations only to find the first no longer offers it, the second was broken and the third is charging .50 cents and wouldn't you believe it I didn't have any cash on me. Next day I bought the compressor in pic from Sears for $89.00 which fits in a very small corner of my garage w/ a 50 ft air hose so it can reach out into my driveway. Isn't worth squat when it comes to blowing stuff around my vac & blo works much better for that but for filling up and topping off car/suv tires it's perfect. Also bought a Digital pressure gauge and some other goodies.
Re: Anybody tried nitrogen on their tires?
Quote:
wtsnet said:
Doesn't anyone use a foot pump any more?
Much easier than having to wire up an electric compressor, and saves the planet too
"wire up"? What do you mean having to put the plug in the wall cause that's about all the wiring needed.
Besides I stopped using a foot pump right after I stopped blowing air in with my mouth even though everyone here knows how much hot air I can blow!
Re: Anybody tried nitrogen on their tires?
Quote:
wtsnet said:
Works in a black-out too....
And sure beats having to drive to the gas station.
Got this for black-outs. 5500 watt generator. Runs a couple of refridge's/freezers, couple home theater units, lights and some other stuff around the house including the compressor if I needed it till the power goes back on. Will do until I find the permanent unit I want. Geez why do I have pictures of all this stuff? lol!!
Apr 17, 2007 6:52:32 PM
- 69bossnine
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Re: Anybody tried nitrogen on their tires?
Michelin Pilot Sport PS2 - $474.00
Porsche Carrera S, decently optioned - $92,000.00
Owner out in the driveway, flailing away at a foot pump to save the planet, only to hop in and speed off full throttle in his premium-fuel-thirsty-leather-lined-totally-wretched-excess sports car?...
PRICELESS...
Porsche Carrera S, decently optioned - $92,000.00
Owner out in the driveway, flailing away at a foot pump to save the planet, only to hop in and speed off full throttle in his premium-fuel-thirsty-leather-lined-totally-wretched-excess sports car?...
PRICELESS...
Apr 17, 2007 6:56:15 PM
- 69bossnine
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