The physics at the moment is the same between the two, provided you turn on BOP and reset all tuning settings. It would be bizarre to make it different. And lobbies aren't sport mode, so practice lobbies would also have different physics to the actual races. It would make zero sense to have two different sets of physics built into the code.There is no comparison between Sport mode with human competition & arcade mode with AI. It you can't win in arcade mode, you don't need to be in Sport mode.