These are hints for the AI not to or less brake at around the track.
BMW Z4 GT3:
Times with ai at 100% and no traffic
- (without hints): 1:57 min
- (with hints): 1:51 min
Just drop the folder in the content folder.
Check out my other mods as well: http://www.racedepartment.com/downloads/authors/ltcars.247335/