The tape on the tires is for the pit crew to align the tire on straight during a pit stop. Sometimes the center of the fenders will have a piece of tape as well.
Firestone tire is a NASCAR sponsor. Some of the cars use firestone tires other cars use NASCAR tires. Firestone also sells NASCAR tires in addition to their own brand.
They fill their tires with nitrogen.
For maximum grip.
Yes the new tires are faster and do not slip.
About 1500 dollars a set.
The biggest tires that are common have about an 29" outer diameter.
Probably sell them as souvenirs.
It is just a form of celebration.
Unlike the Nascar Nationwide Series, the Sprint Cup Series does not use rain tires.
Goodyear just pulls them out of the truck at random.