It also is the highest revving turbocharged motor in the competition with its flat-plane crank design allowing 8500 rpm. The M838T won the category that BMW's S65 V8 dominated for five years partially due to the S65 V8 ending production and partially due to improvement to the motor.
In the McLaren 650S output is raised 650 horsepower just as the name implies. McLaren did not just raise boost but revised the cylinder heads and exhaust system. The 650S motor also gets news cams.
The engine is compact and lightweight at 438 pounds and manages to be clean as well without relying on direct injection. The port injection motor's days may be numbered buy McLaren reminds us just how damn good it can be.