I’d probably be better off just getting rid of all the empty paper coffee cups behind the driver’s seat.
A Smart car might float away in a strong wind that might come handy in a traffic jam. LOL!
Yes - but the potential savings is much less than 2lb per wheel.
Googling suggests that a typical passenger car tire encloses a volume around 30 liters or so. At full inflation, this would be something under 100 liters of air at standard atmospheric pressure. Replacing this with helium yields a mass reduction around 100 grams - less than a quarter of a pound.
That’s a nonzero but tiny benefit - probably undetectable by any normal means.
True, but you’re not going to eliminate two pounds of unsprung weight by filling your tires with helium instead of air; the difference is likely to be measured in grams.
When I was a kid some of the bicycle shops offered to fill your bike tires with helium to reduce weight. I think it was directed at the serious bikers, not kids – folks who look for the minuscule differences. How well it worked, I don’t know – as remarked above, helium is smaller than oxygen or nitrogen, and will more easily sliup out through gaps that would retain heavier and larger gas molecules. I suspect their tires went flat faster.
There may be some use for gasses other than ambient air or helium in car tires, although again the actual benefits may be negligible for the market in its entirety. Several years ago Ferrari Racing experimented with and had some success using a refrigerant gas (HFC) and CO2 mix in their F1 cars. What they found was that the mix helped lower the internal temperatures of the tires by dissipating heat through the wheel which reduced blistering and extended the longevity of the tires, considerable factors in a race. Considerable enough that McLaren cheated and was caught trying to steal their secret and incurred an enormous fine. However, if this had commercial potential it certainly has been slow to roll out to the masses.
Make my car lighter? I’ve already got a lighter in my car, although I mainly use it to plug my electronics in. I think they’re calling it an accessory outlet now.