OREANDA-NEWS. July 22, 2016. The M5 Pure Metal Silver Limited Edition is a mouthful, but it's also guaranteed to be a handful. Its 4.4-liter, twin-turbocharged V-8 now puts out 600 horsepower and 516 pound-feet of torque, thanks to higher boost pressure and modified engine components. Non-special-edition output is 560 hp and 500 torques. 60 mph arrives in just 3.9 seconds. The only transmission available is BMW's dual-clutch gearbox.