Restrictor class is an age limited class (A Class with restricted orifices on the intake to reduce horsepower.

As far as “picking” a class, the reason all these kids are coming out of micros are so good is they enter all classes in a night, A-class, wingless, and multi (outlaw). They get in three times the laps in a weekend with the same equipment.

Start out slow and work your way up based on your budget (and stamina!)