Same as above but our middle class ,no box(9.50-13.99) is called Pro.
Super gas cars (9.90 index) are door cars and roadsters only. A roadster is a topless car that the driver sits on the left side like in a stock vehicle.
Super comp (8.90 index) is door cars, roadsters, altereds (see my pic) and dragsters.
Roadsters are left hand sitting and altereds you sit in the center over the drive shaft.
NHRA rules, It costs alot more to run 9.99 or faster that to run 10.00 and slower.
When you break that 9.99 barrier you have to get a NHRA license, physical, get your chassis certified every 3 years, and the safety equipment can be more expensive.