Hi
Are you using a performance txt file within gpx patch
Like
** GP3edit - Performance File **
[Team #00]
Name=Mercedes,Mercedes
Performance=810,816,1000
First Driver=44,Hamilton,16128,192,16192,192
Second Driver=77,Bottas,16059,192,15897,192
etc as you can change the values to make it more competitive.
also the Physics files has different values for player and the AI.
maybe have a look at these