https://www.gamespot.com/articles/ps4s-free-gran-turismo-sport-demo-is-out-now-for-a/1100-6453911/

Gran Turismo Sport is just days away from release, but you don't have to wait for launch in order to try it out. Sony has released a demo of its signature racing game on PS4, although its availability is more like that of a beta, rather than a traditional demo.