Show off your muffler mods

[huskihl]

i would think that would be the case eventually. but where is the line when is enough, enough.

It’s much bigger than what most people think. And there are lots of variables like deflector size, location, size of the screen. A 1” hole behind a 1“ wide x 1/4“ tall deflector doesn’t flow nearly as much as a 1 inch hole with no deflector. And if the screen is stacked straight on top of the hole, it only flows from 25% to 50% the size of the hole because of the screen

 

[farminkarman]

It’s much bigger than what most people think. And there are lots of variables like deflector size, location, size of the screen. A 1” hole behind a 1“ wide x 1/4“ tall deflector doesn’t flow nearly as much as a 1 inch hole with no deflector. And if the screen is stacked straight on top of the hole, it only flows from 25% to 50% the size of the hole because of the screen

Well stated!

 

[pbillyi69]

thats good info right there

 

[huskihl]

Tiny saw

 

[pbillyi69]

its prolly your big fingers... lol

 

[Stump Shot]

Tiny saw

View attachment 367974View attachment 367975View attachment 367976View attachment 367977

...in really big hands no less. Work looks good!

 

[TreeLife]

I love this thread

 

[pbillyi69]

yes the work looks great

 

[Stump Shot]

550 mkII


MS361

 

[pbillyi69]

550 mkII
View attachment 367979

MS361
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how do you keep that screen in the tube in the 550?

 

[Stump Shot]

how do you keep that screen in the tube in the 550?

It's jammed between two different sized tubes and all three are silver soldered in place at the can. If it gets dirty it can be hit with a propane torch in place for cleaning the ss screen.

Edit; it's 45% silver brazed not silver soldered. I misspoke.

 

[pbillyi69]

copy

 

[pbillyi69]

i have been trying to figure a way to attach a screen to a pipe on a muffler that Pa Dan made for me. not so much for the spark arrest as for keeping crap out when not in use. i put a rubber stopper in there now.

 

[huskihl]

its prolly your big fingers... lol

No lie

 

[pbillyi69]

if you could get your finger in there you woukdnt be able to get it out. lol

 

[Partner]

and this is cylinder 064

 

[Stump Shot]

No lie

View attachment 368006

By eye, that's a 25cc thumb!

 

[Ketchup]

i would think that would be the case eventually. but where is the line when is enough, enough.

I was more saying that I don’t necessarily lose power if I go too big, just don’t get anymore. It’s debatable though.

Like @huskihl said, there are a lot of factors. I think somebody posted some cut time tests where their 660 got slower after about 150% of cylinder outlet. But how the outlet is designed, where it’s located and what the port numbers look like will all matter.

Someone mentioned recently that they ported an exhaust really high but the saw performed well as long as the kept the muffler outlet restricted. That may be, but I can’t see that being the strongest porting strategy.

Generally, if you have a direct, unrestricted shot that’s greater than the exhaust outlet, going bigger has no benefit.

 

[Stump Shot]

572xp

 

[Squareground3691]

Little Mod , just need to braze in .