My last three planes ( giant scale) have lived through my COWL-EC-TA-MIES: Cutting cowls to fit big,fat mufflers. It doesn't matter what method I use, templates, dummy cowls etc. They all seem to wind up looking like "Freddies last victim" .SO, can anyone give me a heads-up on trying to design and fabricate my own muffler systems especially for gas engines. I know that pylon racer's must use some kind of flex pipe and all I am seeking is some advice on method & materials. BTW; it's not a money thing I just want to see if it is feasible. Thanks for any input. Mikel-T