What is the ruling on insulting the police who are trying to prevent "tafheet" (drifting/reckless driving), and is insulting them like insulting the Hay'a (Commission for the Promotion of Virtue and the Prevention of Vice), and does insulting them reach the level of disbelief (kufr) because of that?

Abusing is a transgression, and fighting a Muslim is disbelief. A believer is not one who curses, slanders, speaks obscenely, or uses foul language. The police's prohibition of reckless driving (tafheet) is a form of enjoining good and forbidding evil. Reckless driving is forbidden, and cursing the police because they prohibit it is impermissible, but it does not reach the level of disbelief.