There are really a great number of games available that are comparable to the Gran Turismo 4 PSP ISO game. However, out of all of them, the Gran Turismo 4 PPSSPP game is the one that is considered to be the greatest and is played by a lot of people all over the globe. The games that are comparable to this version of Gran Turismo 4 for PSP ISO are listed down below. A game of Motorstorm RC, a game of Driveclub, a game of Project Gotham Racing 2, and a game of Forza Motorsport.