Benefit of MAP vs MAF

[M3takesNYC]

I know we have only MAP sensors and a similar engine e60 M5 as well as the new M5/6/XM5/6 all have MAF sensors. Also evolve sells a MAP conversion for the MAF e46 and e60 m cars, so what is the real deal on why they choose MAP over MAF?

I was surprised that the new M cars have a MAF sensor so clearly MAP is not "better" and I thought the one real difference was an improved throttle response, although I am not sure why. However if that is the case, you would think surely bmw would have used MAP sensors in the new turbo M cars as throttle response was deemed to be very important to them.

[CanAutM3]

My guess here is that on a NA engine, the mass flow of air entering the engine can be directly correlated to the throttle opening and RPM, so these 2 parameters combined with air temperature are sufficient to calculate the quantity of air entering the engine. However, on FI engines, the manifold pressure for a given RPM and throttle opening can vary depending on how much boost is provided by the turbo. Here, mass flow varies according to throttle opening, RPM and boost. Hence the reason for a Mass Airflow sensor on the FI engines. However, in my opinion, the system used on the S65 engine is still better as it provides less restriction in the intake tract; just much more complex to execute on a FI engine.

[Edjay]

Most MAP sensors works with vacuum. Its alot easier to use a MAF sensor when you have boost. IMO theres no real advantage from one or the other. Just preference in tuning.