Investigating way my cutting legs did not work found something interesting. If you mount the reedblock it is blocking almost the whole C-port.
It is almost completely closed.
However if you look to an original SP setup, it looks like the reedblock is designed different and it makes sure the C-port is open
Look at this, this can't be ideally
It blocks it almost completely
Here with reed petal pressed open.
It shows that it is getting tighter when fully open
A bid harder to see, but the arrows points the legs the marked area is the blocked C-port
The interesting thing is on a SP engine is, it looks like they moved the reedblock to free up the C-port (Ore designed different)
Now in this setup at least it has a change to work
Look at the space it has