Someone mention /6 drag racing?

Never heard of this.
How should I imagine this goes about...?
Are all the racers getting a Slant6 engine tied to their rear bumper and they have to drag it along the track during the race or what...? :) :)

The best part is when I drive past all the gas stations with all the 440 cars at the gas pumps while getting 24 MPG on the cheapest gas around.
Other than the A100 guys, I guarantee the slanters will have the most fun.
Half the displacement but double the fun.