Hi All,
Just saw a picture of a WW2 R/C fighter plane with no muffler. The engine was completely in the cowl, with the muffler output slightly less than flush with the cowl. Obviously the engine will produce more noise, my question is is there a loss of power? Can the engine be damaged running w/no muffler? I would think that the engine was designed to give full power with the muffler. If this is a viable alternative I would like to use the configuration for a more scale look in my Red Box Top Flite Mustang, and maybe my OV-10 Bronco.
If noise is not a factor for flying, is it feasable to not use the muffler for a more scale effect, or will I be damaging the engine?

Thanks for your opinions/advice.