Bump.
Well, my daughter did race last year and again this year and really likes it.
The track is about 1/4 mile long and the cars reach speeds over 30 mph. You race your opponent twice (once in each lane). The time differences at the finish are tracked for each of the 2 races. The winner finishes (wins) by times measured in the hundredths or thousandths of a second.
It's a more specialized event then I thought.
If done properly, the cars are seriously "tweaked". They do things like put micrometers on the axles/spindles to check/adjust tow-in and such so the tires are perfect.
Prior to the race, cars are torn down, inspected, re-assembled and impounded to assure everything is right. The drivers are also put in the vehicles and get markings on their helmets that match to a corresponding spot on the car. This assures the drivers can't/don't shift their weight during the race to change their speeds.
First thing on race day, all cars (with drivers in the seat) get weighed. All must be within 1 pound. There's also limits on front and rear axle weights.
When paired with your opponent, you have to start by swapping 2 tires with them. After the first race, you swap all 4 tires for the 2nd race.
Just before your race (when being loaded in the shoots), tires are cleaned and other things for aerodynamics are adjusted. A pebble on a tire or a wrinkle in your shirt is enough to loose a race.
Here's a couple pics.
My daughter is the 2nd driver (sitting between the red and blue car)
Here's a pic of the track (and if you look closely, there's 2 cars coming down the hill). The truck in the rear is pulling a trailer and is used for taking the cars (4 per trailer) back up to the top.