Grass culling is broken - no idea what is going on.

This Setting here: [Edit, stupid image is not loading… the “Cull Distance” Setting for Foliage-instances]
https://www2.pic-upload.de/img/32661048/Unbenannt.png

Is broken, since 4.14.

I used the exact same grass in my first game, with the exact same settings as i am doing now - but it is unplayable now.

Framerates drop far below 30 now, and i can not fix that, until i either all grass in the game.

Any ideas what is going on there? (Foliage-scalability settings also do not work anymore, neither in 4.14 or 4.15p4)