Muffodication ms460

[Slamm]

I don't think it makes much difference.

On the 441CM's I just hogged out the stock opening on the bar side of the saw, but I'm not for doing that so much anymore, because I use my saws for felling mostly and I cut low. So all of that exhaust just gets pushed right into the ground/roof flares and I have to breath that crap.

My other saws have the stock hole and then a large port on the starter side and this is much better for felling, because the exhaust just flies up the tree trunk and I never smell anything.

Sam

 

[old-cat]

Couple questions to the OP and other 046/460 owners. I just got 2x 046's in the shop and rebuilding both. I was just wondering if adding a second port would give any gain over opening the stock slot. I plan to open the diverters inside the muffler and extend the exterior baffel forward to protect the handle. And of course I'll open the OEM exhaust port in the muffler. I do need to know if one large opening would be just as good as two medium size openings? Neither saw is ported, one has stock P&C and one has a nikasil BBK on it.

Comments?

I am almost certain that opening the muffler decreases fuel efficiency more than power increases.
The more you open it up the more you have to richen the carb, because the gas is going out the exhaust. Most people here say modding the muffler wakes the saw up. I say that it wakes up the operator!

I think MMs are better for strato-charged saws.

 

[like2surf]

I am almost certain that opening the muffler decreases fuel efficiency more than power increases.
The more you open it up the more you have to richen the carb, because the gas is going out the exhaust. Most people here say modding the muffler wakes the saw up. I say that it wakes up the operator!

I think MMs are better for strato-charged saws.

Bigger exhaust opening. Needs more fuel=More power. More efficient use of the cc's you have to work with.

 

[nstueve]

You could also make the argument that a free flowing exhaust increases the saws ability to keep a higher RPM in the cut making cut times quicker... IE: less time cutting = less fuel used. Besides that you can also make the case for cooler running temps causing less wear and tear on the saw. Hot saw = shorter saw life.

Acceleration is better too...

 

[Slamm]

A 2 stroke makes the most power (100%) without a muffler .......... unlike a 4 stroke. This has nothing to do with Piped 2 strokes.

So that said, opening up a muffler is getting it closer to no muffler and that is going in the direction of maximum power. That said, there is some compromise between noise level and power output and someone else can fill in the blank but there is a point where you can open the muffler up and you are mostly getting noise and very little of the added power for the noise heard.

Engines need to get air through them or they don't work. A plugged up muffler can't flow and therefore you don't need much fuel to go with very little air flow, hence the need for richening up the mixture when MM'ing a saw. They can do more work in a shorter amount of time, therefore they need more fuel.

Sam

 

[Tree Sling'r]

Lower (cut out) the baffle inside the muffler to the bottom of the exhaust port on the cylinder. That will help a little as well.

 

[Gjt1980]

Another miserable day here so the ms460 still sittin lookin pretty. I want to get her dirty

 

[rullywowr]

Personally, muffler mods have never impressed me much.....especially considering how they are all hyped up by members on this site. Its not going to blow your socks off......

Tony

I beg to differ...depends fully on the saw. On my 550XP I am still looking for where the F my socks went after the MM!! :confused2:

 

[z71mike]

A 2 stroke makes the most power (100%) without a muffler .......... unlike a 4 stroke. This has nothing to do with Piped 2 strokes.

So that said, opening up a muffler is getting it closer to no muffler and that is going in the direction of maximum power. That said, there is some compromise between noise level and power output and someone else can fill in the blank but there is a point where you can open the muffler up and you are mostly getting noise and very little of the added power for the noise heard.

Slamm - Is there any need for back pressure? Like if there is some back pressure present, maybe it slows the exhaust charge, allowing a small amount of time for a more complete burn? I might be talking completely out of my a$$........ just throwing thoughts out on the table. I keep counter-pointing myself in my head.......yes/no/yes/but/$hit

OP - Good work on the MM. Should definitely help op temps. You can always mess with it again later if you really need to re-route fumes away from your breathing space - personal preference based on job and usage.

 

[Mastermind]

That's gonna get hot on the brake handle......

On a stock saw a dual port cover would have been a great idea.

 

[Gjt1980]

That's gonna get hot on the brake handle......

On a stock saw a dual port cover would have been a great idea.

I have got a little cut time on the saw now since my mod and as soon as i shut it down after cutting the plastic handle is warm no where near hot enough to melt it

 

[4x4American]

You are not in a position to notice the difference a muff mod makes, because you haven't broken in and run the stock saw extensively, thus establishing a baseline of performance before doing the muff mod.

Be that as it may, you can trust that the MM will increase performance by a relatively small but still noticeable amount. I do agree with Tony that we've seen too many people doing muff mods and making the resulting performance molehills into mountains, but any Stihl with an MS in front of the number will deliver real gains from a muff mod. Not like what you see with porting in conjunction with the MM, of course.

must be the ms stands for muffler sucks!