Paul,
            What I originally intended to do was to put a single 2.5 inch hushpower muffler under the fuse and another 2 feet of tubing behind that, but am thinking now of putting in a Y splitter and sending the exhaust into two 2 inch mufflers, so that if one melts, at least I have another outlet.  Probably a little more drag, but the sportsman only cruises at 140 Kts anyway.  How mad am I ?   Neil.

Yes that is a pretty good idea. If you can pop out to Perth
Ian Beadle has a real quite RX8 motor in his RV6.
http://www.youtube.com/watch?v=XgLw3a8DZgM

Paul Lamar