From Archive: Mufflers for Cavalier by Edwin Smith

[Club Archivist]

Hey gang,

I love our little Cavalier 18' . Great power, etc, etc.

It would really be nice to hear a little better. Overton's has inline mufflers for this beast. I haven't checked West Marine yet. Here's the question . . . At ~$100 x (2) for muffler system, is it efficient ?
Does it cause havoc with back pressure ? Does it really muffle or am I chasing an ideal & blowing money that could utilized better ? Surely, out of the wealth of knowledge of our group, somebody has done this or knows of someone. P.S. I apologize to all the purists out there. I assure you ALL modifications I have made to this wonderful old woodie can be reversed & I have all the parts !.

[Club Archivist]

I have utilized mufflers on V8 engines before. This was on a Gar Wood speedster we built. We sit on the rear (only) seat and it is fairly loud with the tips maybe 3 feet from your ears. We put mufflers on the boat. It did not change the way it sounded but it was quieter for sure. Still had a great rumble though so there was no going back to no mufflers.

There are some good designs out there that have no virtually no backpressure. The best designs are from www.vetus.com in my opinion. The latest designs use a series of baffles (not in the air stream, however, you can look staight thru them). What the baffles do is cause the cooling water to "atomize" in other words, break the flow up into a spray. It is this water spray that does the majority of the quieting inside the muffler. We experimented with various types. The long (4' or so) ski boat mufflers we did not like near as well as the compact (maybe 18" long) ones from the vendor above, www.vetus.com. We have also experimented with their waterlock mufflers. Virtually dead silence you can almost just hear the water streaming out. If anyone is interested I can get vetus stuff for better price than is shown on their website and happy to provide quote.