Hi guys,

I Have a tower 75 in a seagull extra. I have had nothing but problems since I maidened it. So far 4 deadsticks resulting in damage and a few others that I recovered without damage. I have a jtec pitts muffler on it. I can adjust the mixture to run a nice high speed and idle good too. I can hold the aircraft vertical for 30 plus seconds with no sagging. Then I take off and it all goes downhill. Anytime I pull positive Gs the engine sags in RPM's. Today I ran the engine up on the ground everything was good and as soon if I took off it died again. Luckily I have adopted the habit if taxing all the way back so I was able to save it before the trees this time. Also when in the air it sounds like a 4 cycle type sound anywhere in the midrange. I was thinking this was because the muffler has two outputs but I was wondering if that sound is normal. (It absolutely sings a solid 2 cycle note at WOT)

Any ideas on keeping it running would be great.

FWIW I am running 15% Omega and McCoy plug with an Idle bar.