There are the Factory Stock and Factory SS classes. My engine guy and I went to the Gators on Thursday this spring and there was a pretty good crowd there. The announcer called it "Hardcore Thursday" with a better than anticipated turnout, but the once-in-a-lifetime conditions (~-2900' DA) didn't produce record times since most shutoff around 1000' to avoid the HP hit. It doesn't seem like NHRA wants to promote the classes much. The shootout races are heads-up but are eight car fields from what I've seen. I think there are enough cars out there to make a 16 car field.