No there is no maximum in NASCAR.
No, they do not. Manual transmissions are used in Nascar race cars.
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Kyle Busch is the all-time Nascar Nationwide Series race winner, with 66 victories. It used to be known as the Busch Series.
They used to race on dirt tracks, and they had bad cars.
Nitrogen
slick tyres are used.
Slicks.
nitrogen
Many industrial supply companies will sell you compressed tanks of dry nitrogen that would be suitable for tires. For normal auto tires, regular air is fine, but nitrogen is often used to inflate the tires of race cars and airplanes.
No, there is not. Gateway Motorsports Park (formerly known as Gateway International Raceway) has not held a Nascar sanctioned event since 2010. Both the Nascar Nationwide and Truck Series used to race at Gateway. The track now hosts a race in the NHRA Full Throttle Series.
Not any more. "Stagger" is a technique used to make race cars with bias ply tires more stable. You put either bigger tires or higher tire pressure on the right side. Sprint cars and other series where they're not trying to "make everyone equal" use bigger tires; because NASCAR has always mounted the tires for you they put more air in the rights. This has naturally led to some of the more vicious wrecks in the history of the sport - if you are running five pounds of stagger and accidentally put a right-side tire on your left front, you go straight into the wall at full racing speed. They don't use stagger with radial tires because it doesn't do anything for you.