Tracking race positions

Heres the details of the problem -
- Anywhere between 2 and 8 racers on a overhead track
- The track can be any shape/size, and corners, straights etc can intertwine or run close to each other
- Players pass through checkpoints on there way round the track

Here is the problem -
- I need to track the position of these racers as close to real time as possible as they move around the track, as in 1st, 2nd, 3rd etc including when racers over-take each other.

There are a few options/solutions I have thought of or had suggested to me but none of which are a sure solution. So I am posting here hoping someone can come up with some ideas of how this can be achieved.

Remember that you can't just track the distance between the racers, because you have to take into account the corners etc of the tracks.

Thank you for any help or suggestions people can provide. :)

Nobody can help with this?? Really? :(

One method could be to have an active object shaped as a line and with the hostspot at the center. Start of level position this on the leading car, and have it always set it's position to the front of the car and th angle to 90 degrees of the car's.
When another car passes the car, it will touch the active object, so now make the line always follow this car instead.

That's the best I can think of, you can do the same thing with some clever math, but this is easier :)

popcorn are you crazy?

spike i would use the pathfinder object; and work out the fastest way to the last(or next) checkpoints distance.

also as popcorn said math is possible; i would blend the distance from several positions taking each over key points distance in to consideration, it may be some ugly math but it is possible.