Nitrogen in Car Tires (Page 6): “They stay pretty even while running.”? I suspect you omitted a word but in case I’m wrong, what’s a “pretty” tire?😳...

Dannj

Flyerace wrote:

When my vehicle hasn't been used, the tire pressure runs 34-35. Once on the road, that moves to 36-37. They stay pretty even while running. The standard on the door states the tire pressure should be 35, but they still look brand new at 37. (not a big diff, but just advising the little diff between a cold tire and a warm tire)

My car is just 1 year old this month. Just over 10,000 miles.

“They stay pretty even while running.”?
I suspect you omitted a word but in case I’m wrong, what’s a “pretty” tire?😳

TriX Loc: Raleigh, NC

HOHIMER wrote:

Catering to an implausible social construct that pure Nitrogen is required in tires driven in a conservative way. Race cars, maybe, but not necessary for a day to day driver. Nitrogen tends to not change the tire pressure as much (as the tire heats and cools during hard driving), as contrasted to air.

IF that’s true (and I’m not sure it is), my guess is it’s due to the moisture in air as compared to nitrogen. If I remember my chemistry, the Universal Gas Law states that all gases expand equally with an equal change in temperature (chemists and physicists please correct me if I’m mistaken)

petrochemist Loc: UK

TriX wrote:

IF that’s true (and I’m not sure it is), my guess is it’s due to the moisture in air as compared to nitrogen. If I remember my chemistry, the Universal Gas Law states that all gases expand equally with an equal change in temperature (chemists and physicists please correct me if I’m mistaken)

I was thinking much the same, neither air nor nitrogen are 'ideal gases' but they won't differ by much.
Moisture on the other hand expands dramatically on vapourisation (far more than any other common material). I'm fairly sure just drying the air used to fill the tyres would have the same effect as using nitrogen.

Harry0 Loc: Gardena, Cal

jerryc41 wrote:

I mentioned the friend who has been looking for a ... (show quote)

Racers (cars and bikes) used nitrogen because it didn't have oxygen, and kept the tire pressure steady. Er. Going to Laguna, it's @ 50 when you start, and soon your'e racing on asphalt and it's 90 out. Then the folk doi ng 30mph on the 405 for a 5 mile trip to work wants it. Marketing happens.

TriX Loc: Raleigh, NC

Harry0 wrote:

Racers (cars and bikes) used nitrogen because it didn't have oxygen, and kept the tire pressure steady. Er. Going to Laguna, it's @ 50 when you start, and soon your'e racing on asphalt and it's 90 out. Then the folk doi ng 30mph on the 405 for a 5 mile trip to work wants it. Marketing happens.

Please see my post above concerning the ideal gas law or general gas equation (pV=nRT). Nitrogen and air (which is mostly nitrogen) expand the same with a change in temperature. It’s the fact that the nitrogen has essentially no moisture, and the water vapor pressure change is what’s eliminated. There are other reasons why race crews like nitrogen. It’s inert and less flammable than oxygen, which could be helpful in an accident in the pit or during a wreck.

sodapop Loc: Bel Air, MD

And to recommend it in ordinary vehicles is a marketing ploy to obtain more money and totally useless

TriX Loc: Raleigh, NC

sodapop wrote:

And to recommend it in ordinary vehicles is a marketing ploy to obtain more money and totally useless

Agree.