Oculus Rift DK2 and UE4 4.3: problems with Oculus Runtime 0.4

I still can´t get rid of the stuttering. It doesn´t occur when walking straight forward, but is extreme when turning.

The rift works in extended mode. I is set to 75 Hz in the Nivdia control center, and there I also activated Vsync for all 3d applications.
I have to say, that I can´t find out how to open the console to show stat fps. I set my Keyboard from German to English(US), but still
nothing happens when pressing the ~ key in standalone game??
But in my editor window in simlutate mode I always get 55-60 fps. In the realistic rendering demo, as well as in the simple content expample scene.
I´m running on a GTX 770 4gb. How am I supposed to get 75fps? Do I get more fps when playing in standalone mode and not in the editor?

Is the Vsync the cause of the stuttering? Do I have to type in the HMD Vsync ON console command, what I cannot do, because I´m to stupid opening the console? :wink:
Sorry, I know I seem to be missing basic things, hope someone can help.