Best Answer
If you install all three discs, installation will require 22GB of hard drive space. Alternatively, you can install each disc individually as you progress through the game and uninstall once you have completed that portion.
To install Rage to your Xbox 360 hard drive, do the following:
1. Insert disc one into the disc drive. After you insert the disc, the default option is set to automatically start the game. When this occurs, exit the game and return to the Xbox 360 Dashboard.
2. From the Xbox 360 Dashboard, go to My Xbox.
3. Select the game you want to install.
4. Press the Y button on your controller.
5. Select Install to Hard Drive. You will see a progress indicator displayed while your game is being installed on your hard drive.
Note: discs 1 and 2 are used for the game's Campaign Mode and disc 3 is used for online multiplayer modes only.