This Mazda RX-8 was built by Dr. Danish Speedshop. The car originally came with a 1.3 L RENESIS two-rotor but is now powered by a turbocharged Honda K20 inline-four. The owner drove the car with the factory RX-8 six-speed manual but eventually swapped to a BMW E93 M3 dual-clutch transmission running a DKG transmission controller. They also replaced the factory differential with one from an RX-7. Watch the RX-8 drive around Ring Knutstorp in Kågeröd, Sweden.
Source: Dr. Danish Speedshop FB page via Piotr