McLaren has unveiled the 788HS, a high-performance version of the 750S that will be limited to just 200 units.The twin-turbocharged 4.0-liter V-8 now produces 777 horsepower (37 more than the 750S).The 788HS also produces 10 percent more downforce than the 765LT, with a new S-duct hood, front splitter, F1-inspired diffuser, and a raised active rear wing.