The primary differences lie in the engine... They are the same basic block, but the CCR is factory rated at 806bhp, and CC8S is factory rated at 655bhp. The weight is also a bit lower.
The CCR has a Twin Screw Supercharger set-up, as CC8S is a single. Either way, the cars fly seriously.
There are also small differences, wheel size, factory standard and option packages, etc.
To see the complete differences, please visit the Koenigsegg comparison page.
Koenigsegg CC Cars
... O... And I have the second post
-Wes