ChiefK,

The muffler shown on the Webra is an old SEMCO. I’m certain that they are not currently manufactured, but I had one in a box, and picked the one in the photo below up at an on-line auction site (ya, that one). The photo below shows two versions of the SEMCO muffler, the “Flow Through” (115gr), and the sexy dual tail pipe (76gr). The Flow Through, on the right, is actually a tube inside a tube (you can look into the hole in the front, and see right out the back), with the inner tube being drilled full of holes. I believe that they all require an adaptor, but the ENYA adaptor that came with the dual pipe is only a fraction off, and could readily be tweaked to fit the Webra. Performance wise, the Flow Through provides very little restriction, but also, very little silencing. I haven’t run the dual pipe, but it is closed in the front like most modern mufflers, unlike the original SEMCO flow through.

That being said, I haven’t currently flown with either of the SEMCO’s.

Also pictured are an OS Max muffler (135gr), and a MVVS muffler (69gr). Interestingly, both the Max and the MVVS have the same bolt pattern. I drilled and tapped this particular Webra without much difficulty, and the result with about 15 flights are no loosening or leakage. I did a little reading, and am comfortable with the thread engagement, and being able to tighten the bolts as required without stripping out the block. Rather easy to do once I came up with the courage. The aluminum block drilled and tapped nicely.

Still debating the fillets. I would put them on after I finish fiberglassing anyways to avoid having to sand around them.

Good looking bird you have there. Hope mine finishes up as nice.

Doug