Has anyone added aftermarket exhaust to a chainsaw?

[Ausfahrt]

I have three chainsaws. An old Stihl 025 from the 90's that has served me well and still runs great. I recently bought an Echo CS-271T top handle limbing saw that I keep in a sheath on my Kubota tractor. It is super handy and light and I love it. My third saw is a Stihl MS311 that I want to ask about.

I bought it about five years ago to help me deal with my wooded acreage here in Vermont. It's bigger and more powerful than my old 025 but still only has a 20" bar. I live on a dirt road that is not maintained by the local municpalities and my neighbors and I had to deal with a rather large downed tree in the road last winter. We eventually got it cut up but a 24" bar would have been really helpful.

So that gets me to my question. Chainsaws that come with 24" or longer bars are generally professional grade and I'm not willing to spend what it takes to buy one that I may or not need. I just bought an aftermarket muffler for my MS311 to help it handle a larger bar and I'm comfortable with the carb tuning but has any one else gone this route?

 

[97K15004WD]

Depends on how restricted it was previously. A pipe will help, but only a little. Porting is the way to go.

 

[JohnnyJohnson]

You'd better make sure that isn't an EPA violation!

 

[UncleDave]

I have three chainsaws. An old Stihl 025 from the 90's that has served me well and still runs great. I recently bought an Echo CS-271T top handle limbing saw that I keep in a sheath on my Kubota tractor. It is super handy and light and I love it. My third saw is a Stihl MS311 that I want to ask about.

I bought it about five years ago to help me deal with my wooded acreage here in Vermont. It's bigger and more powerful than my old 025 but still only has a 20" bar. I live on a dirt road that is not maintained by the local municpalities and my neighbors and I had to deal with a rather large downed tree in the road last winter. We eventually got it cut up but a 24" bar would have been really helpful.

So that gets me to my question. Chainsaws that come with 24" or longer bars are generally professional grade and I'm not willing to spend what it takes to buy one that I may or not need. I just bought an aftermarket muffler for my MS311 to help it handle a larger bar and I'm comfortable with the carb tuning but has any one else gone this route?

View attachment 184049

Yes, not mine but a few buds have done it.

Took a bit of fiddling to get them tuned, but in each case the saw picked up top end- especially with a sectioned expansion pipe, but the saw becomes unwieldy with a big pipe sticking out the side.

 

[jeepman3071]

Yes. I usually just do a muffler mod to make the muffler less restrictive, you can notice an improvement in throttle response and a bit more torque in the cut usually without being as loud as a pipe. The pipes sound cool, but any neighbors that can hear your saw will hate you.

 

[wag123]

You'd better make sure that isn't an EPA violation!

Why?

 

[JohnnyG]

I've seen chainsaws with stinger pipes installed! These are for competition saws of course, so YES!
Think of 2 cycle motorcycle racing bikes if you don't know what I mean.
Looks like your solution will degrade performance significantly.

 

[zzyzzx]

An electric chainsaw doesn't need a muffler.

 

[Rand]

just buy the right chain. if you need a huge bar you can compensate for not having a big motor with a skip chain.

Thats a 59cc motor and specs upto a 20" reg chain.
you could run a 28" with a skip chain as long as the oiler will oil enough.

24" with reg chain is doable too imo.

my 2 cents worth of non-pro advice.

 

[jeepman3071]

I've seen chainsaws with stinger pipes installed! These are for competition saws of course, so YES!
Think of 2 cycle motorcycle racing bikes if you don't know what I mean.
Looks like your solution will degrade performance significantly.

His pipe won't degrade performance, but it will be pretty loud for the amount of performance gained over a stock muffler or a muffler that has been opened up a bit. If he lives in the middle of nowhere and uses hearing protection it won't really be an issue though. All of my saws have muffler mods.

 

[wag123]

A straight pipe in place of the muffler is not the way to extract maximum performance out of a 2-cycle engine, the exhaust system needs to create a resonance that provides both back pressure (for higher compression) and cylinder scavenging alternately. This is why the highest performing 2-cycle dirt bikes and snow mobiles all use expansion chamber exhaust systems. The mufflers are carefully designed by the better chainsaw manufacturers to create this resonance.

The Story of How a German Missile Scientist Revolutionized the Two-Stroke Engine

The design has since been iterated upon and improved, but Walter Kaaden’s development started it all.

www.popularmechanics.com

 

[Ausfahrt]

A skip chain is an interesting suggestion. I am not familiar with them but I will look into it.

 

[jeepman3071]

A straight pipe in place of the muffler is not the way to extract maximum performance out of a 2-cycle engine, the exhaust system needs to create a resonance that provides both back pressure (for higher compression) and cylinder scavenging alternately. This is why the highest performing 2-cycle dirt bikes and snow mobiles all use expansion chamber exhaust systems. The mufflers are carefully designed by the better chainsaw manufacturers to create this resonance.

The Story of How a German Missile Scientist Revolutionized the Two-Stroke Engine

The design has since been iterated upon and improved, but Walter Kaaden’s development started it all.

www.popularmechanics.com

It isn't a straight pipe though, the chambers of the pipe are different sizes, there are many saw builders out there on youtube running similar style pipes.

 

[Blueshound]

Came here looking for how to make it quiet. I'm in the wrong place obviously.

 

[ironman_gq]

You can run a 24" on that saw, skip chain will help immensely. They also have semi-skip which is between a regular chain and a skip chain. Pull the muffler off that saw and take a look at how choked up it is, I'd be suprised if the factory outlet is a 3/8 hole. Open that up to a at least 70% of the exhaust port size on the cylinder, retune the carb as necessary you will likely have to remove the limiter caps on the adjustment screws. I use a sheetrock screw and twist it into the plastic cap, align the "tab" on the cap with the slot in the carb body and pull them out, they do not need to be reinstalled. Invest in ear muffs, it's going to be loud. If you want some directions just google "MS311 muffler mod" you can also look at what people have done to the 291, 311, 391 saws or the 290, 310, 390, 029, 039 or any other saws in that family they are all the same saw body with different cylinders on them. You could actually put a 391 top end on that saw if you needed more power after the muffler mod

 

[IndyIan]

Came here looking for how to make it quiet. I'm in the wrong place obviously.

Ear plugs and muffs! My little saw had a catalytic converter on it which made it pretty quiet really, but then it plugged up, and now has a small hole drilled through it and is "normal saw" loud.
With low profile thin chain a little saw can make pretty decent cuts in soft wood I find. But for hardwood firewood, a bigger saw makes the job fun instead of a chore.

 

[IndyIan]

I have three chainsaws. An old Stihl 025 from the 90's that has served me well and still runs great. I recently bought an Echo CS-271T top handle limbing saw that I keep in a sheath on my Kubota tractor. It is super handy and light and I love it. My third saw is a Stihl MS311 that I want to ask about.

I bought it about five years ago to help me deal with my wooded acreage here in Vermont. It's bigger and more powerful than my old 025 but still only has a 20" bar. I live on a dirt road that is not maintained by the local municpalities and my neighbors and I had to deal with a rather large downed tree in the road last winter. We eventually got it cut up but a 24" bar would have been really helpful.

So that gets me to my question. Chainsaws that come with 24" or longer bars are generally professional grade and I'm not willing to spend what it takes to buy one that I may or not need. I just bought an aftermarket muffler for my MS311 to help it handle a larger bar and I'm comfortable with the carb tuning but has any one else gone this route?

View attachment 184049

Full skip square filed chain should be quite fast with a 24" bar for your saw. I only round file on my chains, but touch up every 2-3 tanks of gas. A sharp well setup chain can make a huge difference.
I think you can get a 24" bar for a low profile chain too, so a much narrower cut can help too. The logosol chainsaw mills used these to save wood and time. Maybe there are skip low profile chains too?

 

[John105]

Has anyone gone as far as true duals? It would, and would not, surprise me if it exists.

 

[Cujet]

I did the common "muffler mod" on my 346XP Husqvarna saw. It helped. But that was already a rip-snorting 50cc pro saw.

The idea that one can tune a small muffler's shape to optimize output is in error, simply low restriction will get you most of what is available. Nothing short of a proper expansion chamber works to make "big power". And, quite simply, this is not practical for the average saw user.

 

[Ausfahrt]

Thanks to all who chimed in here, I appreciate it.

My MS311 only gets used in situations where my 025 is too small or underpowered and I've probably run less than ten tanks of gas through it in 5+ years. My plan is to leave the 20" bar & chain on it most of the time but get a 24 or 25 inch bar with a skip or semi skip chain for when I need it.

I do plan to mount the muffler and see if it makes a difference and mess around with it a little since I now own it.