I'm making a F1 simulation game, and I'd like to know which one is the best way to create racing tracks (in this case for a f1 game). :)

Whatever works best for your engine.

Honestly, there is no best way of doing it. You could generate the tracks as a nurbs loft and then convert to polygons, or you could just create it in a level editor with BSP construction. If you're going to be using realistic physics, then you'd probably want to use the first method, taking into account the speed and mass of the cars as they go around the curves and elevate the curves accordingly to offset drift.

Really, I don't think that there is a best way. No matter what though, draw the thing out on a piece of paper and work out the physics before you start modeling.

mmh... I see. thanks !

If you plan on creating the track as static meshes that you can export from Max this tutorial might help:

http://www.inspiredrealms.com/racetracktutorial.html

I created it a while ago for another poster who was asking how to make a track in Max. It seems that this question comes up a lot on this forum.

We used 3dsmax to design lots of tracks.
The hint will be to use spline path with loft modificator.
Copying shapes over the path allows you to tweak track very easy in real-time, and build very smoth turns for high speeds.