Re: NA fueling...
You need to think of the engine as a properly sized system of parts all feeding a 3.2 liter air pump. The compression ratio and the cams determine what it can use, throttle body controls the air flow in and the fuel pump/nozzles control how much fuel.
These represent maximums and computer controls where you are in that envelope. You have to figure that MB engineers knew what they were doing in selecting the operating points inside that envelope though they had to consider things other than pure power e.g.:
Cost
MPG
Torque curve
Emissions
Warranties
Accessories
Model positioning
Point is that the engine is a system of parts and rarely can you just change one piece for a material gain.