In Gran Turismo 6, there is a distinct difference between "Save Data" and "Game Data." Understanding this distinction is the first step in protecting your progress:
A typical file size ranges from 1.5 MB to 4 MB. It resides in the “Saved Data Utility” folder under the PS3’s Game column.
The game ties the save to your specific PSN account ID. To use someone else’s save, you need to re-sign it.
Here is where many players hit a wall. Some is locked. Specifically, save files that contain paid DLC cars (like those from the “Ayrton Senna Tribute” or “Ferrari F1” packs) or online trophies have copy-protection flags.
Both are managed via the PS3 XMB under Saved Data Utility (PS3™) and Game Data Utility respectively. Critical Backup and Transfer Rules
This requires both PS3s to be connected via an Ethernet cable (a direct LAN connection). This is the most reliable method for migrating copy-protected data.
Edited saves will not earn trophies retroactively. You must trigger trophy conditions again (e.g., buy a car to get “Living the Dream”).