chainsaw mods.

[easymoney]

i ran up on this link showing chainsaw mods. what do the members think about it.
https://www.youtube.com/watch?v=fiA2zd1omQg&app=desktop

[justallan1]

I feel the folks at Stihl and Husky know more about making a chainsaw than I do and I stand way better odds of it working if I leave that to them. I'm certainly not saying it wouldn't work, but I'm not finding out either.
I'd also be concerned about lighting the woods on fire, whether it would or not, and know for sure in California you couldn't use a saw on any public lands with a modified muffler.
I look at it the same way I see folks buying a $40,000 truck and then adding $6,000 worth of crap to get 3 more HP out of it. Why not just save your money and buy what you need to begin with.
Just my thoughts on it.

[sawguy21]

Some of us don't know to leave well enough alone. ;D Hot rodding goes back to when the first car owners wanted to go a little bit faster and farther and there is nothing wrong with that. A lot of manufacturers took notice and incorporated some of these mods into their products making better vehicles. It isn't for everyone, 98% of the buying public is perfectly satisfied with the factory offerings but that other 2% (not mentioning any names) views that as a just a place to start.

[Jiles]

Nice video.  I know that most people adjust their "H" screw the way this guy did.
However, I have been doing this for many years and I would never consider holding a throttle wide open continuously while making the adjustment. Way too much movement inside an engine.
Instead, I simply hold the throttle at WO and determine what adjustment is needed. While the engine is idling, I make that adjustment and try at WOT again until I get it right.
Just my opinion and I am sure most of you disagree.

[21ftnitro]

Some newer saws have a rev limiter and can't be adjusted using the no load wot method anyway. You have to actually cut into something. Stop and make the adjustments and try it again. Anddyshine77 has a good video on this.

[Bilge Rat]

There is more to a proper muffler mod than just drilling holes in it.
First take the muffler off the saw and enlarge the existing holes. On that saw you can add a few more holes but don't go crazy.
Be sure to wash all the metal shavings out of the muffler before putting it back on. A 2 stroke sucks air back into the cylinder and will pull anything into itself chewing up the motor.
This is a good reason to keep the screen or another more open screen/spark arrestor in place.

You need to remove the limiter caps to get the proper tune after any mod.
Knowing what a properly tuned saw sounds like in and out of wood is important. Having a tach is a good idea too.

You tube has all kinds of things on it. Some sound good but are not the best thing to do without understanding why you are doing it.
Notice the first vid was a stock saw then the second was the modded saw with a RS chain.
A good sharp chain is the first best thing you should learn to do to a saw. If you want it to cut fast you need a sharp chain.

Opening up the muffler will help a saw breathe and run a little cooler. A sharp chain will cut faster.
Having a longer bar on a saw can slow it down if the powerhead is not strong enough to pull it.

Having a few ported saws myself i can tell you the real power gains are in port timing and compression.
Even on those saws a dull chain will make them look very slow.

[JohnG28]

https://forestryforum.com/board/index.php/topic,69759.msg1046894/topicseen.html#msg1046894

I did a thread a while ago on doing a muffler mod to a 361. Same process works with many other saws with some slight variations.

[nk14zp]

For the little mill I had, I added 3 stops that were vertical and adjusted with a "T" bolt. I liked them way better than the stock ones that flipped up. I put the first two at 2' apart and the 3rd at 6' from the first and had the 3 of them pretty much centered on the tracks.
The factory clamp/stop assembly made it impossible to have stops for loading logs was also one of the reasons that I made them.
I'm sure I'll build about the same thing for the new mill also.
I don't have any experience with the screw type clamps, but am wondering if they don't get in the way of the carriage on large logs?

How is modding a chainsaw any different than modding a sawmill?

[AdkStihl]

How is modding a chainsaw any different than modding a sawmill?

You hang out over here too........

[Andyshine77]

The saw porting business is alive and well, I've done a bit of it myself. Ported saws are mostly for enthusiasts and pro loggers who want to up production, it's not for everyone. 

justallan1. Take into concentration manufactures have many constraints they must work around, from EPA regulations, product cost, to mass manufacturing variances. Most who actually know what they're doing, are often, simply removing these limitations and optimizing what is already there. For example, I've seen the squish band on two saws of the same make and model, have squish band clearance differences of nearly .030" that can make a difference in compression of 40psi or more, compression = power.

Now when it comes to opening up the muffler on a saw, it's not only allowing these EPA restricted engines to breath properly, it also reduces engine temperatures, particularly the exhaust side of the piston. Myself and others use spark arrestors for fire reasons mentioned above. With that said they're more sparks thrown off the bar and chain than from exhaust gasses. Most fires started by saws came from the older saws with the exhausts that were on the bottom of the saw, exhaust on saws can glow red after long cuts.   

290's gain quite a bit of power with a simple muffler mod, go for it, just make sure to retune afterwards, and never to run a saw unloaded as long as the guy in the video did, a few seconds is all that's needed.

[weimedog]

Ditto Andyshine77.

One additional thought, a twist on that theme... I've been working with a few loggers this last year. AND how their operation is structured determines their interest in modifications. For example: One logger I work with does a lot of his own saw work, and his help also is "motorsports" oriented therefor quite interested in the saw he runs. THOSE guys are pushing me for more performance every time I either work on one of their saws or when they come around for "BS" time.

Another logger has a mix of mechanical harvesting and saw work. Typically his saw guys really are just young folks from the local farm community looking for some work and not particularly interested in the business or the tools used. Turn over is high a the work is long hours, nasty conditions, and very hard. Also a lot of the saw work is following the feller buncher and bucking the logs to the right length. He typically gives me saws with crush damage or the last one where one of the guys literally twisted off the air filter on a new 372xt breaking the air horn/filter holder along with damaging the intake boot as well.... HE is not particularly interested in adding another 300 dollars to the cost of his saws....they need to start, cut, and not stop until the job is done. Reliability and toughness to survive in that environment is way more interesting to him. Therefore I don't wouldn't even consider adding more variables into the equation for his "work" saws, stock is how they come; and stock is how they leave this shop. Now his personal saw.... that's another deal.

So for all the theory about saw mods adding one thing or another to the performance of a saw...that's all true. And the "cooling" thing with exhaust mods theoretically might even add a little life....and that's up for debate. It certainly won't hurt when done right. (I'm not a fan of random holes and holes sizes...they have to be a part of a plan) Stock is what those who are in the true business of manufacturing and supporting a dealer network believe are their best chances of providing a blend of performance and reliability in the market place deliver. The compromises have a lot to do with manufacturing tolerances... (Notice the new Husqvarna's like a 562 typically have pretty tight "squish" band measurement's...) and EVERYTHING to do with cost of supporting through warrantee, dealer networks, and the wide range of capabilities of those who use and service their products as they go through their service life. And as the previous post pointed out, some of the most productive modifications are really about bringing a saw closer to the "better" side of the tolerances. And old concept "blue printing" comes to mind. But as smart as those who port saws and build saws are, its really tough to out engineer the true engineers for that blend of performance and reliability over the life of a saw. That's my humble opinion.

[JohnG28]

Excellent posts Andyshine77 and weimedog! 

[nk14zp]

How is modding a chainsaw any different than modding a sawmill?

You hang out over here too........

HI!!!

[Andyshine77]

Great post weimedog!! It's nice to have input from the loggers, and how they see things. 

[justallan1]

For the little mill I had, I added 3 stops that were vertical and adjusted with a "T" bolt. I liked them way better than the stock ones that flipped up. I put the first two at 2' apart and the 3rd at 6' from the first and had the 3 of them pretty much centered on the tracks.
The factory clamp/stop assembly made it impossible to have stops for loading logs was also one of the reasons that I made them.
I'm sure I'll build about the same thing for the new mill also.
I don't have any experience with the screw type clamps, but am wondering if they don't get in the way of the carriage on large logs?

How is modding a chainsaw any different than modding a sawmill?

What I had changed on the sawmill was just the clamping system to hold the logs.
For those of you that know about doing proper mods on your saws, more power to you. :D
For me, I can live with how it was originally made. I've always wondered if a lot of the mods done on any engine will shorten it's life?

[CCC4]

How is modding a chainsaw any different than modding a sawmill?

You hang out over here too........

HI!!!

Hiya Zippy

[Andyshine77]

I've always wondered if a lot of the mods done on any engine will shorten it's life?

A muffler mod will normally extend the engines life, and normally adds some performance. A properly ported work saw will last just as long as a stock one, and this has been proven.

You have no need for a ported saw, it's not your thing, and that's fine. With that said, don't dismiss them outright. I bet you'd change your tune if you actually ran one. Having the power of a large heavy saw, in a smaller lighter saw, is very attractive when you're working with a saw 8 hours a day, every day.

   

[CR888]

Firstly l own/run ported saws and they are fun and great. But thinking porting a saw will extend its life is just plain silly unless its a heavily restricted muffler with maybe a cat inside. Increasing compression, lifting the powerband, increasing working rpm by a few thousand all create more stress on cranks, bearings, pistons, cylinders. I cannot believe some that post so often simply don't get this.

[Andyshine77]

Firstly l own/run ported saws and they are fun and great. But thinking porting a saw will extend its life is just plain silly unless its a heavily restricted muffler with maybe a cat inside. Increasing compression, lifting the powerband, increasing working rpm by a few thousand all create more stress on cranks, bearings, pistons, cylinders. I cannot believe some that post so often simply don't get this.

I personally don't consider some of the mods you mentioned, normal in a woods ported saw, some builders do. Most builders are pushing things far passed what I call a work saw. A lot of the crazy compression numbers these guys are getting are totally unnecessary in a work saw. So I agree with you.

Muffler mods are a different story, most modern EPA saws have extremely restricted mufflers, so yes a muffler mod will most definitely extend the life of the saw.       

[Ianab]

Yeah, you are starting to talk about a "race" saw when you up the revs and compression.

Any engine design is a compromise. Manufacturers have to comply with emission and noise regulations, while still making a saw that's reasonably powerful, AND reliable. Now once you get your hands on it, you can then choose to ignore the emission and noise part of the equation.

So the "muffler mod" becomes practical. You decrease the back pressure, increase the noise, and the saw tends to spit out a bit of un-burnt fuel like an old school 2-stroke did. But you can adjust the mixture, and have the saw making a bit more power at the same rpm. and probably running a bit cooler. Buy some good ear muffs, and it's all good.

Porting involves changing the port timing. A bit more complex, but small changes can give a bit more power, and wont kill the saw. Like fitting a "warm" cam to a 4 stroke car engine. That's a "work" saw. You still expect it to last for years, just if goes a bit better. 

But if you go past that by upping the compression and increasing the revs, then it's like building a race car engine. How long do you expect it to run for? A race season? A single drag meet? The more stress you put in the engine, the faster it's going to wear out. Some of these guys could be replacing pistons and rings every week for all we know. Sure the saw cuts cookies fast, for 1/2 an hour....  If that's what they want. good on them. I'm sure I could get my Toyota to do a 10sec 1/4 mile. Just I'm not sure how long for   ;) :D

[ktowne030311]

So I was at the stihl dealer getting a few things for my ms290 project to finish it up. I told him that my next thing I wanna do I port my muffler. He told me not to, he said that it will scream, how ever it will not be as reliable, and I would blow it up. So I have opted not to do any porting.

[CCC4]

Can you not just buy a dual port cover for that size saw?

[JohnG28]

ktowne, I don't believe that to be true at all.  Andyshine and Ianab's posts explain it very well.  As long as you don't go crazy and take a golf ball sized hole out of the muffler it's going to help it out a lot.  Read my thread on muffler mod for my 361, it will go right along with the 290 also.  It is going to give you more power with keeping the engine cooler at operating speeds as long as done right, which comes from properly tuning it after adding the second port on the muffler. 

Ian, I REALLY want to see that 10 second Corolla!!  :D :D Been looking for a way to get a little more from my Camry!  :D :D

[HolmenTree]

The video showing  the MS290 muffler mod was way overdone  with too many holes drilled.
To that guy he fooled  himself  thinking it had more power with how noisy  it became, but if he used a stop watch in before and  after  cuts he would probably find it cuts slower.
These plastic bottom end consumer grade saws are basically a throw away disposable  item. The time and expense to rebuild one and if you can find the proper  silicone  sealant makes them a poor choice to work on.
Your  far better off to find a decent saw like a 044AV  or 034Super to tinker with and you'll have something  more functional and worthwhile  in the end.

[Ianab]

Ian, I REALLY want to see that 10 second Corolla!!  :D :D Been looking for a way to get a little more from my Camry!  :D :D

Getting a bit off topic, but here you go. 8.3 second Corolla. OK it's got a Nissan engine running a LOT of boost, but it's still street legal.
http://www.youtube.com/watch?v=lHsq8_o52qM

My "Corolla" will do about a 13 sec 1/4 mile, that's factory standard.  It did come from the factory with a Lexus 350 engine (big V6). Toyota in Australia briefly sold a Camry / Aurion with the same engine, super-charged. But it never really caught on, just too much power for a front wheel car.  :

But it's like going crazy with your chainsaw, mod a machine too much, and iit becomes increasingly more impractical for every day use.

[JohnG28]

 :D :D Nice video Ian! Lots of boost on that ride!

[fordf150]

Every engine has a horsepower/hour ratio. At some point in the curve the extra HP starts reducing engine life. Where that point is differs on every engine and what part will fail is different. Opening a muffler up "should" yield extra power and increase the life of every engine. Some saws benefit more from it than others. 290/310/390 have proven to benefit greatly from freeing up the exhaust but the other side of that is a Dolly 6100 that has no measurable increase.

here is an easy way to understand the hp/hr ratio.
7.3 powerstroke engine  and assume in all examples that maintenance and use remained the same
stock 240hp it will last 350k miles
increase HP to 300 and it still lasts 350k miles but does everything better
increase it further to 400 and suddenly the life expectancy drops to 250k miles
take it on up into the 500hp range and you might be doing good to 100k miles out of it.

i just made up some numbers for that but the basic idea still applies. the more extreme you go the better chance you have of drastically reducing engine life.

adding extra ports or enlarging the stock port works the same way. up to a certain point you add hp and reduce heat but after that point all your doing is adding noise, increasing fuel consumption, possibly reducing hp as your fresh fuel mix flows out the exhaust port

i have a ported saw and every other saw i own except the 5105H has a muffler mod.

[Andyshine77]

So I was at the stihl dealer getting a few things for my ms290 project to finish it up. I told him that my next thing I wanna do I port my muffler. He told me not to, he said that it will scream, how ever it will not be as reliable, and I would blow it up. So I have opted not to do any porting.

Your dealer is an idiot.

RPM's can be controlled by tuning, and you're not going to be spinning crazy rpm's in the cut anyway. I know guys running ported saws in production felling for years cutting 10,000+ trees. The average Joe firewood cutter will likely never wear out a good saw, ported or not.       

[fordf150]

 

So I was at the stihl dealer getting a few things for my ms290 project to finish it up. I told him that my next thing I wanna do I port my muffler. He told me not to, he said that it will scream, how ever it will not be as reliable, and I would blow it up. So I have opted not to do any porting.

Your dealer is an idiot.

smiley_clapping

[HolmenTree]

Yeah but that dealer was talking  about a plastic cased 290 not a real magnesium  cased logging saw. :D

[NCFarmboy]

So I was at the stihl dealer getting a few things for my ms290 project to finish it up. I told him that my next thing I wanna do I port my muffler. He told me not to, he said that it will scream, how ever it will not be as reliable, and I would blow it up. So I have opted not to do any porting.

Your dealer is an idiot.

smiley_clapping

Totally agree!!!!!  on the "IDIOT"!  Every saw I own has a modded muffler and most are mildly ported (the rest will be). 
Shep

[Andyshine77]

Yeah but that dealer was talking  about a plastic cased 290 not a real magnesium  cased logging saw. :D

True, but I've ported them, they run well. The 290 gets a lot of hate, but it's a fine saw for it's intended purpose.

[HolmenTree]

Yes that's  true Andre. I remember   a faller buying a Stihl 039 or maybe  it was a ms390 when they  first came out years ago. He said he didn't  pay alot of money for it so didn't  expect much from it.
But he said he couldn't  kill it and the thing had remarkable  performance.  :D
Even the dealer who sold  him the saw bragged about it to me.

[Spike60]

A great deal of this discussion comes down to: are we playing, or are we working. The hobby/enthusiast world and the real pro world have diverged into two very different realities. And, any comments I make regarding the hobby community are NOT meant to be negative. Heck, I'm as big a saw geek as anyone, so they would also apply to me.

The idea of posting a video of yourself cutting a log to show how good your saw runs is not something that would cross the mind of the average logger. Most loggers that are aware of this stuff think we are nuts. And maybe we are, but we are having fun, right? Most loggers aren't interested in ported saws, but that's no different than most saw users not being interested in what we do. But just like us there certainly is a percentage of loggers who want to run modded saws. They want more power, but don't want to carry the "next size up".

When I started modding saws for local pros, I was surprised at how the word traveled and some of the guys who asked be to juice up their saws. But in most cases, I'm doing this in conjunction with rebuilding older saws. It's not that often that they want me to mod a brand new saw. What I do adds very little time to a rebuild, but that's another story. These guys will not tolerate a huge increase in fuel use either. That's not a trade off they are willing to make. And a basic woods mod will not compromise the life of the saw. And like some guys have already said, it gets some additional heat out of the saw.

Now the hobby side has kind of gone off the deep end with ported saws, and again as has been said, they are crossing the line from work saws to race saws. The majority of the saws built by the well known guys are as much GTG play things as saws that might actually do some work. And cutting one's own firewood isn't a work load comparable to a pro logger or arborist. Especially for guys who split their trigger time between dozens of saws. So, most of these saws get little use compared to saws that exist in the pro world.

And we know how it goes at GTG's. "Here try mine, it was built by Joe" "Wow, that runs great, here try mine, it was built by John". Yes it's fun and all, but in the competitive nature of of these things, Joe's saws better not get clobbered by John's saws. So there is some preassure to notch it up a bit to stay on the lead lap, and we get a little farther away from work saws.

Again, nothing bad either way. But there are differences between a work saw and a play saw, and I think they sometimes get blurred on these forums.

[CR888]

Good post Spike!! Its funny l have a few ported saws and four that were done by different builders all have their signature 'sticker' on them that states 'XXX Performance Worksaws'. These 'worksaws' have all had altered port timing, machining to squishband/basecut, possible ignition advance, muffler mod & increased compression. Some have had carb work and piston alterations. None of these builders claim to build 'race saws' and pride themselves on building purpose work saw. I have a 50cc  ms261 which has had its strato gutted and holds 11500-12500 in the cut opposed to my same stock saw that holds between 7500-9500 in the cut. I just cannot accept these increased performance mods will 'increase' service life.lol But they are fun to run! I like the old 'increased performance equals increased production', it sounds great but they never mention the time its takes to refuel the saw. More power, more fuel equals more fill ups equals more downtime. I can do a lot of work with my stock MS241cm strato sipping saw before a refill and that alone increases production with less downtime. Builders don't like to talk about fuel efficiency, its kinda a taboo subject.

[Spike60]

I agree with everything you say there CR. And 200+ psi compression isn't a friend to the bottom end either.

[Andyshine77]

There have been a few guys that took the time to itemize everything, and in the end they saved time and money with ported work saws. The Bloke who did this is Australian, he was felling hundreds of trees a day for months at a time.

With that said, Spike is correct, for the most part.

[CR888]

Andy, l am not trying to bag what you say, quite the opposite. I always enjoy reading your posts and value the time you take to help others and the contribution you make to this site and other sites, same as spike. 99% of the time l totally agree with your posts and the same goes in this thread. I just post my 2 cents as l see things from my personal experience. You guys amoung many others are what really make these forum sites a good place to be. Sometimes words on a screen get interpreted in ways not intended by the poster and get taken out of context.

[Andyshine77]

Andy, l am not trying to bag what you say, quite the opposite. I always enjoy reading your posts and value the time you take to help others and the contribution you make to this site and other sites, same as spike. 99% of the time l totally agree with your posts and the same goes in this thread. I just post my 2 cents as l see things from my personal experience. You guys amoung many others are what really make these forum sites a good place to be. Sometimes words on a screen get interpreted in ways not intended by the poster and get taken out of context.

I took no offense to anything you said. You and Spike are spot on IMHO.

[so il logger]

Well I use my saw's for a living, And hoping to send a couple to tn for a work saw work over. Any advice? I know that the guy doing the work is top notch. I am not an occasional user, like I said they make my living             

[Andyshine77]

Well I use my saw's for a living, And hoping to send a couple to tn for a work saw work over. Any advice? I know that the guy doing the work is top notch. I am not an occasional user, like I said they make my living             

If the saws going to be used real hard, tell them so. Who is doing the work? What saw are you having ported?

[Spike60]

Andy's right; those guys can build a good work saw and taylor it to your needs, so let them know.

But also be honest with yourself and your builder on things like air and fuel filter maintenance, whether you will buy his recommended fuel and mix it at whatever ratio he suggests and such. Some loggers are great at keeping their saws up; some aren't. I see plenty of both and believe me it makes a difference in a saws longevity.

[so il logger]

I plan to send a new un used 661, and an old non decomp 066 for just messing around with. The 661 will be ran on average 8 tanks of fuel a day 5 day's a week. I tap out my filter every other tank and every evening it get's the compressor cleaning. I run the silver bottle stihl synthetic mix. I mix 4 and a half gall with a 5 gallon mix bottle. At this time I don't want to disclose the builder... I haven't gotten it all set up with him yet.

[Andyshine77]

Most builders recommend mixing fuel at 32:1 that's 4oz of oil to every gallon of fuel. A Ratio-Rite cup http://www.motorcycle-superstore.com/7411/i/ratio-rite-measuring-cup is a must IMHO. If you want to save on mix oil buying a gallon of oil at a time is the way to go, as a gallon Stihl ultra is quite expensive.

   

[so il logger]

Yep, I got a ratio rite cup. For the 2 stroke bike's, but is that rich of a mix really necessary? From the factory they call for 50-1, is what I am going to have done going to alter it enough for that much more oil? The builder is booked until nov, but sound's like he may be able to get mine worked in sometime in may.

[Andyshine77]

Randy will recommend at least 40:1, but 32:1 is his and my preference. 50:1 isn't really adequate in a stock saw let alone one that's had port work. Oil isn't just a lubricant, it acts as a cushion, promotes ring seal, and also extends the life of the crank seals. The difference in longevity between a saw ran on 50:1 vs 32:1 is not debatable. Keep in mind Manufactures are in the business of selling new products, and must meet EPA standards.   

[HolmenTree]

My work saws are factory stock and I run the Stihl full synthetic mix at 40:1
I've heard lots of good stuff about Randy's work , he's very busy as that tell's alot about his quality of work.

[so il logger]

How did you guess who the builder was?  ;) Yes I fully agree with saw longevity with a richer mix, and you raise a good point about the manufacturer's in business to sell saw's.

[CR888]

As Andy says above, its not necessarily the top end that is at risk with 50:1 in a modified saw, for me l worry about the bottom end. And +1 on a ratiorite mixing container, they have the calibration to get accurate mix so you know what's in your saw. Don't forget too much oil can be problematic if your saw is not correctly tuned for the increase in oil making your air/fuel mix lean. Many err on the 'better a little more than less' when mixing fuel but unless you tune your saw accordingly, its a problem. Accurate measurements of oil mean a less fiddling with the little flathead screwdriver. My tip for mixing fuel is to put half the fuel in can then add required oil, shake, swirl, shake, then put the rest of the fuel in followed by a bit more swirling shaking. I get funny looks at the gas station all the time while doing this, don't be deterred!

[fordf150]

Randy also likes that fancy oil.

Seen quite a few with big end rod bearing failures on stock saws. not sure what to attribute it to. 50:1 mix, operator error, or just shoddy quality but 40:1 is cheap insurance that at least eliminates one variable from that equation.

[thecfarm]

CR888,I put my oil on the OWB shelf to get it nice and warm when it's cold. Than I dump it in the gas can and let it drain for 10-20 minutes to make sure I get it all. I use the highest grade I can get at the gas station too. 40:1 too.

[Al_Smith]

I doubt seriously if you will really get less hours with a properly reworked engine as opposed to a stocker .You can actually do more with reworking the exhaust as the rest of the engine plus it runs cooler.Of course it uses more fuel but to get power it takes fuel .

In my little life I rebuild saws from a dealers "dead " pile .Most saws I've seen ,Stihls were cooked from restricted exhausts and most likely low oil to gas mix ratios but that would get into my favorite subject the ever presant war of the oils --ainta gonna go there --this time . ;D