NASCAR is very clear about what teams can and can not do to the tires. Teams may not use any chemical or physical means of altering the tires, which means no siping (cutting grooves into the tires), no chemical softening, not even heat blankets to pre-warm the tires are allowed. Basically, you can’t do anything to the tires. This means that when a tire blows out, it’s the tire’s fault. Right?