RE: CG Super Chipmunk and side-mounted OS-91 Surpass II -- FG Cowling woes
Dwango: No, it does not stick out of the cowl. It lies in the space below the firewall. I used a length of aluminum refrigerator tubing as an extension from the muffler to the outside, in front of the wing. If you assemble your header pipe and muffler loosely to the engine, then you can rotate the engine and adjust the orientation of the muffler, until everything works.
Les