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When I was in HS, we had a half-baked punter on our football team who insisted on filling the punting ball with helium, "for better hang time and distance." He was a real piece of work, and swore it made a difference, but nobody else could tell.

Go figure.

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Yep, the same kind of people buy fuel magnets and intake "tornados"!

Dave

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When the tire heats up, the moisture inside it will vaporize and expand, increasing the tire pressure. By using nitrogen instead of air, we have more control over how much the pressure will build when the tires heat up.

We also use nitrogen to power the air guns for pit stops, for the same reason. Those guns are expensive tools, and the moisture in compressed air would damage them.

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Nascar use's it.....They tweak in 1/2lb adjustments(critcal long run adjustment) so the more stable the inflation gas the better......

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According to the ideal gas law (pV = nRT) there is no difference in pressure rise of the different gases given a constant mass and volume.

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oh, oh, I know this one!

6.022 x 10^23

What do I win?

(It's been about 30 years since my college chem class, and you have no idea how little I get to use stuff like this.)

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Hey, that's Avogadro's Number! One of the few things I still remember from Chem class.

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As for using nitrogen in the air guns, it's not convenience, it's necessity. Since nitrogen is denser than air, you get much more volume of gas going thru the gun when removing lug nuts. More gas means faster rotational rate. Faster rotational rate means nuts get loosened faster.

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Wow, I don't even know where to start. You need to read about Boyle's Law and learn a little about fluid dynamics.

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Little far off? Me just knows what I was told.. I leave all the geeky E=MC2 to the pocket protector types..

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I wonder if Helium would yield abother 1mpg over that?




Here is the deal, Nitrogen makes up 85% of our atmosphere, the air compressor that is used to fill tires up, is compressing 85% nitrogen as it is, that news channel is full of it. There was a thread on this a while back

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Wrong---- Atmospheric air is at best 80% N2, 20% oxygen and miniscule amounts of everything else
the only place you will see 85% n2 is on top of 6-8000 ft elevation and even then theres more He and H cause the molecules are so small and light gravity dont pull em down- see your perodic table of elements, I got one hangs in front of me all night here at work.
N2 and argone are best for intermoleculr space and resisting heat expansion thats why its put in double plane windows to avoid heat conduction.
but as a scientist i cant go along with it inproving milege beyond .10% max as the expansion coefficient will not mathmatically work out unless the tire has a volumetric capacity of over 10 cubic feet.

now on the football nut, I filled a basket ball with 99.9999%pute Hydrogen which has morelift than Helium dropped both from my roof (25feet) off the same tilted board and the H2 ball bounced 10-12" higher after 10 trials, it does work, but most guys cant get 5-9s Hydroged.
isnt chemestry and physics great

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Local news article claimed 1-1.5 mpg improvement. Anyone here tried it ?

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Total BS.

When you just fill a tire with nitrogen it's not 100 % nitrogen in it. There is still regualer air in there. Anyways the expansion of diameter of the tire while hot is mostly a fuction of the humidity of gas trapped in a tire.

I crew on a very competitive local NASCAR crew. We watch the diameter growth of tire with respect to tempurature. Just putting in nitrogen doesn't cut it. We need to PURGE the tires of all their gasses about 3-5 TIMES to get the humity down to 3-8%. We have a special tire air humidity guage to check this.

Now if the tire monkey that mounts your tires uses and bunch of soap and water to mount your tires, you have a bunch of humidity trapped in them.

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Another advantage of filling a tire with Nitrogen is that the itsmolecules are thicker and bigger than air..
So if the tire has a slow leak it takes considerably longer for the tire to deflate.......

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If regular air expands more with heat than straight N2 then you would think that you get better mileage with regular air as the pressure builds and rolling resistance goes down.

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From what I understand it's out of convienence. They have pressurized nitrogen readily available and don't need to have a compressor. I'm not sure what they already use the nitrogen for, maybe someone else does?

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