shorthunter
ArboristSite Guru
That was the 9th or 10th cut on the first tank of fuel, not counting the run time when I did the first few startups. The tank was dry when I pulled the cap
Porting 101
- Thread starter pepsifreak28
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Mastermind
Work Saw Specialist
Oh......I see what you mean.
For starters, it's tuned considerably too rich. Did you put a kit in the carb? Check the fuel line? Tank vent clogged?
Mastermind
Work Saw Specialist
I didn't watch the video. He didn't do anything I could see that would make any improvement in the saw's performance.
shorthunter
ArboristSite Guru
I had it running rich for the first tank of fuel. I will retune the carb next time I get the saw out. Did a pretty mild port job. Finished product ended up about 3.6 mm wider on the exhaust port. Can't remember the other numbers off the top of my head. Very little change in timing, increased transfer volume and knocked the edges off the back of the transfer port wall Figured this would help give beginners an idea of where to start
shorthunter
ArboristSite Guru
I was pretty limited in what I could do with this saw without replacing the stock muffler and intake but I wanted to give it a little boost in performance through increased efficiency. If you have suggestions feel free to share
shorthunter
ArboristSite Guru
good advice mdavlee, that is where I started the process. The way these old Dolmar mufflers are constructed it limits what you can do. Maybe I can get a picture up later. The intake is even more limiting on the 143 but I don't want to pull the intake off just to take a picture
LegDeLimber
Addicted to ArboristSite
She sounded leaner after the chain catch at the 1:31 mark.
shorthunter
ArboristSite Guru
Couple more cuts with the carb tuned a little closer. Still running a 33" Carlton bar with .404 chain, 7 tooth sprocket.
HusqyStihl
ArboristSite Guru
I understand this is an old thread but if anyone has any trashed jugs i would love to experiment and ease into porting or even just smoothing out before i rip into my good jugs. Usually i work with alot of Stihl 029's, 039's 290's, 390's, Husq 51, 55, 261, 262xp, 36, 350, 455, 372.... Hell, i'll take any kinda junked jugs to mess around with if at all possible. Just for continued education and a little experience.... TIA
~Moose
~Moose
Chris-PA
Where the Wild Things Are
I think you be best off getting an entire cheap saw to mess with, although probably something with pro construction (I port clamshells but I'm nuts). Something like an Earthquake or any of the Chinese RedMax clones. Then you can play as much as you want and not risk damaging anything valuable. And if you trash the jug you can get another cheap on eBay and try again. Best is that if you get it right you'll actually have a good tool when you are done.
You could start with a used "good" saw, but parts will be expensive and you'll still be hesitant to try stuff.
Or find the cheapest replacement cylinders on ebay and buy that saw. My jred 625 has a ported huztl 272xp cylinder on it and runs much stronger than when it was a 625. For $30 I didn't care if I killed it. I milled with it last week and it was "acceptable".
Some cylinder kits are cheaper yet.
Not personal experience, but I wouldn't go less expensive than huztl. Reports of poor quality go way up after that
HusqyStihl
ArboristSite Guru
Ive got a couple 290 runners but doubt id wanna port them at first attempt. Maybe if i had some junk jugs to give it a shot first... Maybe ill find some. I do have some recently blown 390 A/M tops. Maybe ill screw with them
My ms310/039 was my 2nd port job. Oem timing was rather aggressive Imo for a plastic saw. Exhaust was at 160° duration before I started. I widened the exhaust and intake to within 1.5mm of the skirt and lowered the intake some. Took that saw and a stock 039 to the pile (both were timed before the mods and we're identical) and I gained about 15%. A few holes in the muffler and enlarging the hole in the deflector are a must.
husqvarna addict
ArboristSite Lurker
Hello I need some opinions on intake port duration. I have an older dirt bike cylinder that I am going to add boyesen ports to it to increase fuel and air into the transfers area and it has reeds on this model. I am wondering if I could add the boyesen ports to a chainsaw piston port cylinder or would it just spit air and fuel back out the carburetor? Has anyone attempted this on a chainsaw, hope to hear back thanks.
Looking for a place to ask this and here looks like a good place.
What do ya'll use to do transfer ports in these small cylinders? I have C.C. Specialties 1MC and 3MC right angle heads I use on boat motors but these are too large for the transfer ports in a 48mm MS360 port I'm wanting to do.
I'm retired now and basically gotten out of the porting business and really don't care to buy their 300AMC @ $400 just to do one or two cylinders for one chain saw. Years back I bought a small pneumatic right angle grinder when they first came out for $100 to play with but that cheap thing broke fairly quickly and I see they are wanting $300 for those now.
I see a lot of people doing porting on here and figure they all can't be in the business with these high dollar tools I've been using and there must be something cheaper that will work for a few cylinders.
I'm new on here and have been doing a ton of searches on a good port map for the MS360 and I've seen several things I have noticed people doing on these cylinders I've never found advantageous to do.
The biggest thing is making the port window in the cylinder larger than the runner going to it. I've seen this on almost every intake port I've seen for this cylinder. My experience has always shown when you have an area that increases in size before the charge inters the cylinder, it lets the charge slow down and fuel separate. This will cause a decrease in torque and will cause large droplets of gas to enter the cylinder that do not burn as well, causing a decrease in power. I have always found it better to have a one or two degree taper into the cylinder with at least a straight runner going to it. No increases in volume anywhere. That and an 80 grit texture on the surface just to create just enough turbulence to keep the fuel suspended in air stream. Never polish and intake runner that has fuel going through it, that does bad things.
Another thing is indiscriminate hogging. Every flake of metal you remove should serve a specific purpose, to increase airflow/velocity. What looks good to the eye might not look worth a darn to the air passing through it. The higher the rpm, the more porting may be required, but a work two stroke will not need same amount of metal removed as a completion/race two stroke and you want to leave as much as possible to get keep the crankcase volume to a minimum. Sometimes to the point of actually going in with epoxy and fillers to reduce the volume. Sometimes on a 10,000 rpm boat motor, I've cut and epoxied enough they don't even look like the same motor inside but on the same motor to pull a skier with, I may do very little grinding, just in some key areas to improve velocity.
What do ya'll use to do transfer ports in these small cylinders? I have C.C. Specialties 1MC and 3MC right angle heads I use on boat motors but these are too large for the transfer ports in a 48mm MS360 port I'm wanting to do.
I'm retired now and basically gotten out of the porting business and really don't care to buy their 300AMC @ $400 just to do one or two cylinders for one chain saw. Years back I bought a small pneumatic right angle grinder when they first came out for $100 to play with but that cheap thing broke fairly quickly and I see they are wanting $300 for those now.
I see a lot of people doing porting on here and figure they all can't be in the business with these high dollar tools I've been using and there must be something cheaper that will work for a few cylinders.
I'm new on here and have been doing a ton of searches on a good port map for the MS360 and I've seen several things I have noticed people doing on these cylinders I've never found advantageous to do.
The biggest thing is making the port window in the cylinder larger than the runner going to it. I've seen this on almost every intake port I've seen for this cylinder. My experience has always shown when you have an area that increases in size before the charge inters the cylinder, it lets the charge slow down and fuel separate. This will cause a decrease in torque and will cause large droplets of gas to enter the cylinder that do not burn as well, causing a decrease in power. I have always found it better to have a one or two degree taper into the cylinder with at least a straight runner going to it. No increases in volume anywhere. That and an 80 grit texture on the surface just to create just enough turbulence to keep the fuel suspended in air stream. Never polish and intake runner that has fuel going through it, that does bad things.
Another thing is indiscriminate hogging. Every flake of metal you remove should serve a specific purpose, to increase airflow/velocity. What looks good to the eye might not look worth a darn to the air passing through it. The higher the rpm, the more porting may be required, but a work two stroke will not need same amount of metal removed as a completion/race two stroke and you want to leave as much as possible to get keep the crankcase volume to a minimum. Sometimes to the point of actually going in with epoxy and fillers to reduce the volume. Sometimes on a 10,000 rpm boat motor, I've cut and epoxied enough they don't even look like the same motor inside but on the same motor to pull a skier with, I may do very little grinding, just in some key areas to improve velocity.
Careful....
One thing you will learn after a few years here is...there is more complexity and technology required in porting these one cylinder wonders than a Yamaha TZ750! Certainly more than those lowly 300plus HP tweaked Mercs!Next.....if you aren't from Ohio or the PNW you probably have the wrong DNA... your going just have to work twice as hard...
last? Why port an saw? Just buy an Echo cs590?
Chris-PA
Where the Wild Things Are
'cause 9k rpm is boring?
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