In FS9 : I can not put my "head" outside of the cockpit. The viewpoint boundary matches the cockpit fuselage.
That's realistic.
In FSX : There is no such behavior, I can put my head outside of the VC quite often. I could virtually be flying next to the aircraft if the TrackIR sensor had a 180� FOV

This is not realistic. How one can get viewpoint boundaries to match VC cockpit fuselage in FSX ?