what version of the game are you using? (188.8.131.52?) and are you using the no-cd fix?
And also, what gamemode? This option is intended for the player-controlled 'track' races.
version used is 184.108.40.206 but no cd fix or anything.
on a sidenote how on earth did you find the stamina value, as I have been trying to look for a number of values but as a lot of them are bars on teh display i don't know how to find them