It was a dark and stormy night. Really.

The wind and rain went on all night and into the day today. I went about my usual stuff and around noon I noticed that the wind had stopped and the sky was getting lighter. Off to the dog track we went. The rain had washed away all the snow except for what the snow plows and blowers had piled up. I brought the 576 Ringmaster and the engine started to go fast after launch again. I changed tanks, same thing. I added muffler pressure, same thing. There was bubbles in the lines so when I got home I removed the fuel system and pressure tested it under water. No leaks. It must be vibration. I took a plastic tank off another plane and put it on and went outside and ran two tank fulls through it. The engine held the rpm and there was no bubbles in the lines this time. I don't have a cheek piece/tripler on the nose of this plane and it vibrates more without it. I also changed to a 10 x 5 prop to get the engine off the vibration point, I hope. If it's not to windy tomorrow I'll give it a try.