The Blackwing is unlike any other V-8 in GM’s current lineup, closer to the high-end powerplants of the German luxury brands than the General’s pushrod offerings. It’s the first twin-turbo V-8 in the company’s history, with an aluminum block and heads, dual throttle bodies, water-to-air charge coolers, and electronic wastegates. In the CT6 Premium Luxury, the engine made 500 horsepower and 574 lb-ft of torque; in the high-performance CT6-V, those figures jumped to 550 horsepower and an astounding 640 lb-ft.The few examples of the twin-turbo V-8 were hand-built in Kentucky, at the Bowling Green plant where the Corvette is assembled. Each engine was constructed from start to finish by a single employee, one of just six appointed to this role. One source estimates that the Blackwing cost General Motors $16 million to develop—around $20,000 per example.