I ran my jj1400 again this morning, first with the single piece tail cone then swapped on the two piece so I make sure it wasn't better matched to the new combustion chamber. Outside temp was 50 - 55 F and humidity was much lower than yesterday when it was raining.

Single cone put out 10 lbs 12 oz
Two piece cone 9 Lbs 6 oz

So the single piece cone is still doing better for me, but it does run hotter at 650c vs 580c with the two piece.

I did find that my case is leaking quite a bit of air at the front where there is a bit of a gap between the screws that hold the case to the diffuser due to the case being too big (or the diffuser too small) I've had this issue with both of the JJ1400's I've had. Can you guys that just got your engines tell if the case to diffusser fit is tighter?

Any suggestions for sealing up the front of the case?

Also, for those interested, I posted a video of my Intro flying with the JJ1400. This was taken last summer/fall so thrust was probably around 8-9 lbs

http://media.putfile.com/jetjoeboomer

Mike