There are newly introduced way of filling the car tiers with Nitrogen yes N and not O..

Also every tire had it's maximum speed hat can run on and it is maintained clearly on every tire.

Please find some links:

http://www.popularmechanics.com/cars/how-to/repair-questions/4302788

http://www.edmunds.com/car-care/should-you-fill-your-cars-tires-with-nit...

http://www.straightdope.com/columns/read/2694/is-it-better-to-fill-your-...

I suggest start a group called "Safety" in QL..

Drive Safe!!