The compression ratio was not included in the press release but we e-mailed BMWNA and did receive confirmation the F10 M5 will have a 10.0:1 compression ratio. Will the pistons be the same as those in the N63? Certainly an interesting question.
The other interesting development is that the F10 M5 S63tu will have VALVETRONIC which BMW claims effectively gives the motor 16 individual throttles. VALVETRONIC being a variable valve control system. The ECU controls engine power directly by varying lift of the intake valves. This system minimizes losses which of course provides a MPG as well as torque boost. The claim is also that it will sharpen throttle response.
Is this car putting out more than just 5 horsepower more than the X5 and X6 M? We think so.