Muffler Mod Temperature and Noise test.

[TyMonk]

Hi,
After time spent skulking around on this site having my questions answered, I decided to create an account and get involved.

I recently got my hands on a Stihl 660 with a mind to milling and the occasional big tree.

Knowing how hard milling is on saws, and wanting to give mine the best chance at longevity, I’ve been looking at muffler mods and their benefits.

However I don’t just want to drill out the output and chop up the baffles and be done with it, I want to find out what difference it makes with running temperature and any change in sound.

I’ve also got a husky 560xp and 236 that I might do the same to, just out of curiosity.

And I want to put up all my results here to help the next guy who decides to have a stab at entry level saw modding.

So my question (finally), am I in the right place on this thread, or should I go somewhere else on here?
Sorry for the waffle

Thanks Lads

 

[TheWizard]

the 560 is auto tune, i personally wouldn't used it for milling. it was designed for felling & limbing (short fast cuts) I would stick to that with this saw.

 

[TyMonk]

the 560 is auto tune, i personally wouldn't used it for milling. it was designed for felling & limbing (short fast cuts) I would stick to that with this saw.

100% agreed, I’m only modding the 560xp and 236 out of curiosity for the temperature change, not for use on a mill.

 

[JIMG]

When you modify the 660 muffler for milling I would suggest you remember to pay attention to direction of exhaust also. The farther away from your face the better.
I have two mufflers for my 394, one for milling and one for bucking and stumping type work.
Also, hello and welcome.

 

[TyMonk]

When you modify the 660 muffler for milling I would suggest you remember to pay attention to direction of exhaust also. The farther away from your face the better.
I have two mufflers for my 394, one for milling and one for bucking and stumping type work.
Also, hello and welcome.

That’s an interesting point, which direction would you recommend?
Would down and outwards in relation to the saw be best? And would it be best to close up the old outlet and open up one larger outlet on the front?

Thanks for the welcome.

 

[JIMG]

Here is a pic of the beauty I hang on the saw for milling.



Here you can just see how the exhaust is aimed when on the saw and milling frame.
(Note the impeccably tidy workshop.)

 

[TyMonk]

Here is a pic of the beauty I hang on the saw for milling.

View attachment 427933

Here you can just see how the exhaust is aimed when on the saw and milling frame.
(Note the impeccably tidy workshop.)


View attachment 427934

Phew that is some rig

I see, so your outlet is toward the bar and downward, meaning that it’s pointing completely away from you when in the milling position.
Did you remove the whole baffle? And do the whole 75% of the inlet thing when choosing your outlet size?


To be fair, when is a productive workshop ever tidy? It looks like a sweet set up to me in there.

Thanks for taking to time to point me in the right direction.

 

[Moparmyway]

I went the opposite side.

To me, getting the exhaust up, out, and away was better than having the saw and especially my lungs sucking it in.

I blocked off the factory exhaust too

 

[TyMonk]

I went the opposite side.

To me, getting the exhaust up, out, and away was better than having the saw and especially my lungs sucking it in.

I blocked off the factory exhaust tooView attachment 428148View attachment 428149View attachment 428150View attachment 428151View attachment 428152

Looks like I’ve got some catching up to do, you lads have some serious machines.

I got a chance today to have the 660 apart for the first time and made a list of needed parts.
She’s in need of a few bits and only came back with 110psi on the comp tester, so I have some investigating to do.
Once I’m happy that everything is where it needs to be, I’ll be carving the muffler and opening it up.

But, I did fit some dogs which look the part, versus none at all.


There’s only a 22in bar on it at the moment but it’s on my list to change.

See @JIMG , my workshop is much worse than yours.

Thanks again to all weighing in.

 

[drf256]

I went the opposite side.

To me, getting the exhaust up, out, and away was better than having the saw and especially my lungs sucking it in.

I blocked off the factory exhaust tooView attachment 428148View attachment 428149View attachment 428150View attachment 428151View attachment 428152

@Moparmyway built both of my milling saws (395/3120) and his muffler exit works very well. Up and away from me. Only have to huff in wood dust now without exhaust.

 

[EFSM]

And I want to put up all my results here to help the next guy who decides to have a stab at entry level saw modding.

C'mon! We need to let others hone their butt dyno!

Actually a scientific approach like this is what advances our culture. Too many people go through school without learning the scientific method.