RE: Yet another DDUST take II
Jay, just an observation. The pipe length on your D Dust looks awfully long. The reason the engine never seems to be "ON" may be due to the pipe length. I race boats as well as fly and we are constantly aware of the pipe length on our boats. It is very obvious when the engine gets "on" the pipe. For instance, my racing 21 marine engine pipe length is 9" from the end of the divergent cone to the glow plug. It turns near 30K RPM. Of course my engine is timed for a pipe so don't expect that from yours, but you should hear it respond. I'd guess that you want to be around 9 1/2". With your setup, that length is measured down the center of the pipe and exhaust header to the plug. Actually, the distance the exhaust flow has to travel to the fat part of the pipe. If you are up to experimenting, start cutting back the header in 1/4" increments till you hear the engine respond. You'll know it when you're there.