Considering that i build alot of my engines from scratch i think i know how to tune a carb. You have changed props to change the load on the engine, which may or may not get rid of a burble but it does nothing for the pressure rise inside many cowlings especially round ones.
The yaks and such are the worst but with the simple tube off the dia cover to the inside of the fuse
solves the issue in most cases. I have done many an engine and used the same prop it was blurbling on and it ran perfect after the tube mod. Just so happens the 35 isnt one of them. Plus its takes quite a lot to stop a gasser in the air and this one just dies W/O any warning.
It almost reminds me of the DLE 30 i designed the new backplate and reed cage for.
Thank you all so far.