Cs-590/620 muffler mod

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STOVE

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I have read a lot on the site about the different ways everyone modifies the cs590/620 muffler. As well as the bold on aluminum port for the top.

Being a one piece design it doesn’t allow for a bark box style.

Has anyone added a universal style port to the side of the muffler? Is it possible with no access to add a nut ? Would be a weld up I assume or a pop rivet .

Would that addition even be worth it?
 
You can just cut a fish gill in the side of the muffler in front of the seam and pry it open, no need to weld.
A lot of guys totally gut the muffler under the stock deflector, it makes them run good but is very loud as the baffles in the middle of the muffler make it act like a tiny little can with the opening back there.
IMO it's better to have an extra opening in front of the baffle plate/crimped seam on these saws instead of a big opening behind the baffle plate.
I have both on my saw, I didnt open it up too much under the deflector and it wasnt too loud or very fast so I added the fish gill and it liked that and runs better.
 
I have a 590 that I bought used that somebody gutted the muffler on. It was obscenely loud so I welded a 3/4” pipe back in the muffler and made a plate with a ~1/2” hole through it to tame it back down. Still flows better than stock, but far less obnoxious.
 
Has anyone added a universal style port to the side of the muffler? Is it possible with no access to add a nut ? Would be a weld up I assume or a pop rivet .
Not used then but kits from Westcoastsaw.com offer that solution. A bit pricy but nice stainless deflectors, 3 sizes choice, or hardware kit only for $7.95.

HW kit comes with a nut (piece) to crush & crimp the blind nut inserts to your muffler shell.

Search their site;

UNIVERSAL POWER PORT​

 
Not used then but kits from Westcoastsaw.com offer that solution. A bit pricy but nice stainless deflectors, 3 sizes choice, or hardware kit only for $7.95.

HW kit comes with a nut (piece) to crush & crimp the blind nut inserts to your muffler shell.

Search their site;

UNIVERSAL POWER PORT​

Egan has a port as well, but I’m really wondering if adding one on the side would add any performance
 
The real benefit is heat reduction. More air volume through a hot tin can reduces temperature.... also pulls heat away from cylinder like a heatsink.

Cooler saw is a happy saw......
Is there a point of diminishing return? Watching some of the Dyno joe 026 videos he mentioned some power loss with too much air flow?
 
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