Mine took 34 Mins on a two and a Half Year Old 60GB Fatty 👍
The Only thing I did to make the Install go a lot easier was I Connected the PS3 to the Internet Via The Ethernet Cable .
Signed onto the PS Network and when I put the GT Install Disc in , it Automatically Said there is a Version Update .
So it Quit the Main Install and Downloaded the Update then Started the Install then I got the would you like to Install the Game Data Message from that Point on it took 34 Mins
Game is Running fine No Problems 👍
Finally went to bed at 3.45am
Woke up at 8-45am switched on the PS3 without the Ethernet Cable Attached and it's still Fine