MKSGR:

Do they mention why there was a "speed limit" Smiley Hopefully not due to reliability issues of the engine...

There is a speed limit at the Ring imposed due to the accident that occurred during a VLN race and killed a spectator.

Apparently they will flatten some crests and insert a chicane in order to eventually remove the speed limits.

http://www.carscoops.com/2015/03/fatal-accident-in-nurburgring-vln-race.html