I purchased a Clubsport Porsche 918 RSR wheel from you. I wish to purchase CSL DD (8 NM). Is my wheel compatible?

  Yes, the ClubSport Steering Wheel Porsche 918 RSR is compatible with the CSL DD (8 Nm) wheel base. 

It is important that both Wheel Base and Steering Wheel are fitted with a matching Quick Release system. The Fanatec ClubSport Racing Wheel Porsche 918 RSR was released with the QR1 system.
The default Quick Release of the CSL DD is currently (July 2024) the QR1 Base Side as well but the Wheel Base can be upgraded to the QR2 system too.

Please notice:
After a Wheel Base was upgraded from QR1 to QR2 the steering wheels need matching QR2 Wheel-Side (adapters) too.