Muffler db

[JPWH 5,308]

I have been working on building a quieter stack muffler. After three muffler builds I have reduced the dB from 86 at wot to 78. All three mufflers run at 69 - 72 dB at idle. I have kept the size the same on each one 2.5" x 8". Using 1.5 od for the stack. This seems to give the best tone. 

[ztnoo 2,298]

I'd say some pics are called for.

Also, what engines are you utilizing???

 

[JPWH 5,308]

Pictures coming soon. I am using my k181.

[jimkemp 525]

if you go with a 3" muffler body you can lower the db level , also the holes in the center baffle make a big difference , smaller holes make less db

[WVHillbilly520H 10,369]

I say put a "Walker" muffler on there and keep a hillbilly at work, anyways working there for 19+ years there are a few different approaches to tuning the db/sound, the baffling also called "louver" tubes have louvers punched in them small to large straight pattern or opposing, then steel wool or high temperature fiberglass packing/wrap, then straight through flow design or internal partitions to divert exhaust flow inlet to outlet in an "S" pattern, then chambered so it's all experimentation till you get what you want, then there's Supertrapp brand where you add or take away discs to change sound/db levels,Jeff .   (Louver tube in a muffler)

[JPWH 5,308]

2 ready for paint. 

 

[WVHillbilly520H 10,369]

Some pics of the "louver" patterns for mufflers, the silver aluminized is a standard single direction flat louver and the gold brass is an unidirectional double flat (more aggressive tone), then there's perforated (round holes punched/drilled) tubes like used in high performance mufflers (no pic),Jeff.