
I get asked this question from time to time and I asked myself this question. On videos we see more than 8 vehicles driving at the same time on the same track on D132.
Exemple : https://www.youtube.com/watch?v=vhdsYjL7wyU
In theory, Digital 132 is 6 players, +1 safety car, +1 ghost car. Each car has a number on the track from 1 to 8 (or 0 to 7 from a technical point of view, I have a doubt). That makes 8 cars on the track.

So what’s this story?!
When you watch the videos carefully and read some of the comments carefully, you will find the answers.
First clue
There are no human pilots seen around the track.

Second clue
Dans les commentaires il est indiqué, qu’il y a plusieurs voitures fantômes.
So ?
Ultimately, you just need to set up multiple ghost vehicles, nothing in the doc says there can only be one car.
You put multiple vehicles on the track and program them all at once following the ghost vehicle setup procedure and you end up with multiple cars that drive by themselves.

Warning
In theory, there are only 8 cars on the track. The track power supply has been sized to support 8 cars, switches, but also accessories such as charging stations for 6 controllers, the starting light ramp, the tower position and for 6 driving positions.
You have to stay within the power supply capacities (amperage). If you add too many vehicles and exceed the power supply capacity, not only will some cars no longer drive fast enough compared to normal but the electronics, which are very sensitive, may go crazy and no longer function properly.
So you have to stay reasonable. The power supply is capable of delivering 3.5 Amps.
On the videos we do not see any videos with more than 10 cars at the same time. Keep a maximum number of 10 vehicles on the track. Which for 4 human players still leaves 6 ghost cars.
Bilan
If there are few of you on the track, having several ghost cars is a good idea. If you are alone it is quite fun. On a rather small box circuit having many cars is not great, it quickly becomes a mess, traffic jams are a constraint. On a large circuit with many switches, it is very good to be able to go up to more than 8 cars on the track, it gives a lot of life. I love seeing the cars change lanes by themselves.