Has anyone heard of this? Apparently from a friend of mine, he recently had his tires filled with Nitrogen which is supposed to help with gas mileage, and decrease wear on the tires. I didn't really know what forum to put this in, so I'll throw it out here. This is the first time I've heard of such a thing, anyone care to fill me in if it's true / useful / possible problems or side effects? -m.
This is commonly done with race car tires. The nitrogen does not expand with heat to near the degree that air does. A race team can regulate the tire pressures very closely during a race using nitrogen. I don't think it would do a whit for gas mileage or tire longevity.
The tire store where I always buy my tires (and always had my summer and winter tires switched before I got the Prius, with its all-season tires) routinely puts nitrogen in all tires. I find it hard to believe that it makes a difference, but they do not charge any extra for it, and they are a good store with excellent service. Of course, if my tires get low I fill them at home with the same stuff I breathe.
Race teams use nitrogen gas since its relative density is comparable to ambient air (molecular weight of 28 versus approximately 29). More important is the lack of moisture which allows the teams to have a more predictable cold to hot inflation pressure response curve. In any event, for street applications this doesn't appear to offer much.
i dont see how nitrogen will keep air pressures more constant. are you saying that nitrogen doesnt heat up like regular air? or that friction is lessen in a 100% nitrogen environment?
The advantage is that 100% nitrogen gas will always behave like 100% nitrogen gas. This removes the variable of moisture content affecting the tire's pressure response to an increase in temperature. Simply put, it makes the race team's life a little bit simpler by taking away a hard to plot variable. However, for those of us living in the real world, this amounts to small potatoes.[/quote]
The nitrogen molecule is more large and it's pass less through the porosities of the tire. My tires are inflated with nitrogen. They have a green valve. 8) I don't know if it's really effective or if it's just a placebo effect. In fact, I think that's specially used to inflate the safe of the tires merchant. :lol:
Simply put, nitrogen will expand less then air. It's been a long time since cemistry class but from what I remember there is about 70% nitrogen, 28% oxygen, and about 2% other elements in "air". by removing the other elements, you get a more consistance change of pressures when the tire and the "gas" insided heat up. As an example: Air at 35 pounds cold, might increase to 40 pounds at 60 mph, where as Nitrogen at 35 pound cold, wouuld increase to 37 pounds at the same speed. There figures are just examples, and not 100% accurate. In racing, speeds, and temperatures are much higher then normal driving. Watch a NASCAR race, and you will see, sometimes they are only running 5 pound in tires, and will make changes in 1/2 pound increments. They take out "air" to get more grip, and will increase pressures to fix a number of handling characteristic.
N2 = 78.08% O2 = 20.95% Ar = 0.93% (Argon) CO2 = 0.03% (equivalent to about 350 parts per million, and rising) The below gases (in decreasing order) are all significantly less percentage wise: Neon Helium Krypton (no wonder Superman bugged out) Xenon Methane Hygrogen Pure nitrogen gas offers a uniform response to changes in temperature and pressure.
