Nuno, my setup looks different than yours. First my pipe appears to be wider than yours. I see you had to add an additional wood pc to seat the rear of your pipe. That P160SX is rated at the same thrust as my K170. I'm not sure that the pipe you have is wide enough for that P160SX. I had Tam's make my pipe for the P160SX and later put in the Kingtech. I just don't like the pipes these chinese companies provide. I don't think they are consistant and have had them fail before. I have no problem with heat on the rear. The plastic tailcones are slightly discolored on the bottom from heat but it's not deformed and the paint isn't affected. There is approx 50 flights on this jet.

Second, the angle of your turbine is much greater than mine. Something doesn't look right here. Can you send another pic showing how the turbine and pipe is mounted?

Here is a picture of my install: