Thanks Russ, ill fiddle with it next time.

Paul, I bought the short one from wren. But it was too long, and I cut a few cm`s off of it.......and then it was too short because of my my case. The fuselage was cmistake. :-)
But I realy dont think it matters anyway. It was cool at all times, even with the less than perfect startup.
I have the one piece exhaust cone of the turbine 10mm from the bellmouth of the pipe.
I have not messured the thrust, but I can feel it has almost too much for the plane