Just so you know.... The intake is shaped that way because the intake charge goes into the crankcase first not the transfer port. The crankshaft is pulling in the intake charge from that side of the intake. Same as the Husky
The 038av is a 62cc saw. The 038 super is 65cc. The magnum is 72cc. I believe I’m close on these numbers. I would have to look them up to give you the exact numbers. And there should be a sticker on the top of your saw telling which version you have.
The 038 design has a ton more velocity in its charge than a 272. Velocity makes a super flat torque curve that typically isn’t hi reving. The 038 has a longer intake tract, and far more restriction with a small combustion chamber and small piston windows, the lower transfers probably lead to better volumetric efficiency. If you could (easily/cheaply) make a full dome 272 piston at .020 squish, my guess is it would spank a 038. Very cool video Tinman!!!!
It's these kind of intricate differences that really change a saw are what gets me so excited about learning how to port, there's so many little things I want to learn and discover
Outstanding discussion, as always! Since I don't have brand loyalty, and own multiple saws in both brands, I'm always looking for the performance qualifiers. For me, it's all about the application. I'll take the 272 all day long for felling, as it's a full pound lighter and just way more nimble with a longer bar. The 038 is a torque monster, but definitely not my go-to for felling. 👍
Thanks for your time you put into your videos its given me the info I needed to tare down my Ms 441 . im thinking of putting a big Boer kit on it to get 77.5 cc out of it but ill see needs a new gas tank because where the vibration rubber piece mouth is busted and their not cheap . thanks again for your videos
Hey tinman that's really helpful and simply informative one of the many reasons I love the content you put out buddy anybody can understand it been studying hard you and the ironhorse now for a good while and getting ready to do builds of my own finally got two 660s I'm gonna build, . One as stock as I can make it the other a family hot production saw oh and hey on topic of fuel my only concern is really the opposite of most timber cutters I want my saws to burn more fuel, lol I rarely carry more than 1 gallon at a time but have been know to carry as much 5 gallons a trip off in the woods so it don't matter either way I do like a saw that revs a little higher I keep chain very sharp, well anyways keep up the great videos my friend latter
A very solid video… it’s also very interesting that these two guys were pretty similar in a many ways and they are just slightly different and those differences are where that additional torque comes from… those transfers make the difference. Those O series Stihl saw’s… the 026- 036…038 they were trying to create a Venturi effect… they wanted a tornado happening in the cylinder… ! We still want that but you don’t achieve that by blocking up your intake…it’s a combination of your exhaust port shape and your upper transfer shape…. Your new charge is spinning and your exhaust is pulling out from the opposite side and that’s what creates the swirling effect… Those intake’s need to have all that blockage removed because we’ve learned that we want an even intake. There’s an issue with those 026/36/38 because you have removed the blockage then you look at the intake boot and they have that same bad shape… there’s 300 series Husqvarna saw’s that have a rubber intake boot!!! 😉👍😂😂😂. You had these two saw’s almost head to head and 52mm bores over a 34mm stroke and then the boys at Husqvarna’s replaced the 272 with the 371-372 a 50mm over a 36mm stroke… 371 being a larger single ring and the 372 being the two smaller rings for the highest compression. I chose longevity over ultimate performance so I always revert my saw’s back into a 371 design with the one larger piston rig … the single ring piston stays cooler and there’s more lubrication and oil flowing around the cylinder walls with a single ring design. The 038 magnum definitely improves with a popup piston… This is definitely a great time to be into chainsaw engine building with all the new Hyway popup piston’s being offered today there’s a lot more piston swapping and upgrading that can be done by guy’s who don’t own a lathe… it’s also great to have these Hyway popup’s for blanks so you have less work to do to achieve your ultimate goal…. I don’t know what it is but having a Husqvarna piston in my Stihl saw or a Stihl piston in my Husqvarna saw is just a hoot for me!!! Swapping parts is great… I’ve never been super brand specific or brand loyal … and with the advent of increased aftermarket support… what you build is what you build! I was running around the junk yard at 8 or 9… by 11-12 I had an old Cadillac running… by about 14 the old codger who owned the junkyard was selling off my runner’s and flipping me cash to keep me working… and he made me a set of my own keys to all the equipment and buildings so I didn’t need to keep Hot-wiring the equipment to be able to get my work done! LMFFAO!!! It definitely beat the daylights out of collecting pop bottles and aluminum cans to earn my money!!! 😂😂😂😂. I was making a $100 dollar to get cars and trucks running! LMFFAO that was a whole bunch of money to me back then!
Same as my 038 mag and 381..each has slightly different perfomance the way it cut the woods..i have them both for more than 10years..Sthil all the time..💪
G'day Tinman, I have come across a number of instances where people have indicated that they had warmed over 038 that ran a single upper piston ring. I have built up a few of these saws now (wouldn't exactly called them "ported"...) but have yet to try one with a single piston ring.
Tinman I have a stihl 038 magnum and it came from the factory with a single ring on the piston and I know it's never been messed with because I am the only owner. I messed with the exhaust opened it up a little bit. Can I do anything else to it without porting. This saw was made in Brazil. The main thing I hate about this saw is the intake filter. Something for you to think about is can you put a 041 or 046 piston and cylinder on a 038 mag so you could have a cold air filter,different carb and cover. This is something I have been thinking on for a while but don't have the money or knoledge. Thanks for your videos keep up the good work from South Carolina
Good points buddy, first build/transformation was a turd saw 029, bb and what I could do to it being clambshell, to 039....good good power but with a 25 heavy bar...man it's a lot for what it is, got to pull out my big nasty fun saw 372xp BB ported and pipes 28 sugi full house, big hard pecan, tree, guy beside me with a 271 just stopped after 1 cut I'd dun made like 6 with no effort lol, I love that saw, i cant put big or enough weight on her to bog her...major torque finally balanced the hp with it but still insane torque, 550 starter rope cord..have to
Air has mass, ramping up an opening allows it to start moving, winding it like a rubber band. That applies to exhaust primarily but also intake. Exhaust exiting can help pull air through the intakes.
The .038 intake is aiming to swirl the air. It might be to make sure bearings are lubed, and the fuel stays at the outside near the transfers. The 038 intake nub is like an inverted walker piston notch which is supposed to ramp the intake flow. Something to think about over dinner.
Airflow, something that a lot of folks don't really think about, but some professions, it's thing that matters. Are the cylinders close enough that one could bolt a 272 cylinder on an 038 or vice versa? I know there is a lot more involved like carbs, etc but that to me would be an interesting way of comparing.
Have you done much work with the new G660 Pro version of the Holzfforma saws??? I just picked one up and I'm debating weather I should have it ported or just run it out of the box. It's going to be my big wood saw so I wouldn't mind freeing up some extra low end torque if possible. Not looking for a hot rod, just a little more grunt than OEM. I plan on running it until the original top end takes a crap, partially to see if they are full of crap about having a better piston and rings... plug I'd like to see how it runs with a pop up big bore top end eventually, but first I want to experiment with it with all it's OEM parts for a little while, at least long enough to get an idea if these are actually worth the extra money compared to the base model g660. What are your thoughts on the subject TinMan???
There are many locals who swear by a 266, but I couldn't sell them a 268 or 272 if my life depended on it. 266's have a much smaller chamber than the later saws.
Cool video. I’ve never run an 038 but my 028 super has way more pull than my 026 for almost the same CCs. I usually just run the 026 though because it’s quite a bit lighter and cuts about as fast unless you’re getting into 12”+ wood.
2000 rpm does some good. My 346xp will cut 16” hard wood faster the a friends 2071 if I keep the rpm up. It tweaks him every time. He will lift a log with his excavator and I get 6 pieces of firewood before he gets 5, then he changes chains or bars and repeat. I have to keep it on screech. I also have a 290, it’s a heavy equivalent to the 346, it has more grunt but less screech.
@@82f100swb True an 028S is few more CCs but it has way more bottom end than an 026, very torquey old saws for their displacement. It is also pretty heavy for its CCs so I usually just grab the 034 or my ported 272 for bigger stuff. This summer I think I’ll port an 026 because like you said, I know it would smoke a stock 028S and make an awesome little saw for most smaller stuff 👍
@@rydplrs71 Yep the little saws sure can cut good with a sharp chain and set rakers. Can’t dog in quite like the bigger saws but if you just let them eat they can do great.
@@rileyjohnston8393 The 026 actually has a 1mm longer stroke than the 028. I have a super and wood boss on the shelf, but it's hard to want to run them. If you poke through my videos on here there's a few of my 026. It's significantly faster with 3/8 than .325 now.
Tinman. Look into conrod crank ratio. It makes a difference at what rpms the best power is produced. Two saws with the exact same port timings and spark timing and same cc, will perform at different rpms. Higher rod ratio better for higher rpms. Lower rod ratio better for lower rpm.
If the 272 piston would work in the 038 I'd give it a go in mine, how do they match up in terms of the piston skirt sizes and orientation related to the various openings in the cylinder?
Tin man id weight that 038 piston. Then I'd grind the casting seams out of it and then chamfer the skirt hard like 1/4" . dime round the skirt corners and then bake the piston and weight it again and run it
Why ? .... More AIR = More TORQUE, keep repeating this simple law of physics until it sinks in! Of course there are those who will say it’s not a “ported saw” UNLESS it’s had machine work done to it , complete and utter rubbish !
Just so you know.... The intake is shaped that way because the intake charge goes into the crankcase first not the transfer port. The crankshaft is pulling in the intake charge from that side of the intake. Same as the Husky
Are you thinking what I'm thinking?
272xp with an 038 cylinder, 372 intake Frankensaw!?!😁
Had my 038 mag since new. I love it dearly!!
I recently acquired an 038. Don't think it's a magnum. What are the differences?
The 038av is a 62cc saw. The 038 super is 65cc. The magnum is 72cc. I believe I’m close on these numbers. I would have to look them up to give you the exact numbers. And there should be a sticker on the top of your saw telling which version you have.
@@greggschultz9256 thanks!
@@greggschultz9256 61.5cc, 66.7cc, 72cc.
You were close enough for govt work.
The 038 design has a ton more velocity in its charge than a 272. Velocity makes a super flat torque curve that typically isn’t hi reving. The 038 has a longer intake tract, and far more restriction with a small combustion chamber and small piston windows, the lower transfers probably lead to better volumetric efficiency. If you could (easily/cheaply) make a full dome 272 piston at .020 squish, my guess is it would spank a 038. Very cool video Tinman!!!!
Great bench talk! And a great comparison/explanation👍
This is a great conversation. There is so much to how a 2 stroke runs. They are simple and complicated at the same time.
It's these kind of intricate differences that really change a saw are what gets me so excited about learning how to port, there's so many little things I want to learn and discover
Outstanding discussion, as always! Since I don't have brand loyalty, and own multiple saws in both brands, I'm always looking for the performance qualifiers. For me, it's all about the application. I'll take the 272 all day long for felling, as it's a full pound lighter and just way more nimble with a longer bar. The 038 is a torque monster, but definitely not my go-to for felling. 👍
Greatly demonstrates brand difference! Thank u for breakn down the difference. Awesome info thank u.
Hey Tinman, thanks form the vid. The side by side comparison certainly tells a story .
Thanks for your time you put into your videos its given me the info I needed to tare down my Ms 441 . im thinking of putting a big Boer kit on it to get 77.5 cc out of it but ill see needs a new gas tank because where the vibration rubber piece mouth is busted and their not cheap . thanks again for your videos
Fantastic info, learned a lot tonight, thank you very much
Finished building my 038. Used a pop up and raised the exhaust. It really rips
Love it friend! Greetings from ole Missouri 👋
Awesome video and info!
After a mild port on my G388 is good for 13k, wich was impossible stoc.
🤝🤝🤝
Hi Tinman
Very interessting. Thanks for your videos. I learn a lot.
Best regards, Dirk
Don’t forget to sleep... You look very tired friend. Thanks for the breakdown.
Really found this interesting thanks!
Hey tinman that's really helpful and simply informative one of the many reasons I love the content you put out buddy anybody can understand it been studying hard you and the ironhorse now for a good while and getting ready to do builds of my own finally got two 660s I'm gonna build, . One as stock as I can make it the other a family hot production saw oh and hey on topic of fuel my only concern is really the opposite of most timber cutters I want my saws to burn more fuel, lol I rarely carry more than 1 gallon at a time but have been know to carry as much 5 gallons a trip off in the woods so it don't matter either way I do like a saw that revs a little higher I keep chain very sharp, well anyways keep up the great videos my friend latter
Great info in this vid!!
Super informative video! Thx!
great job. 038 any of them great saws
A very solid video… it’s also very interesting that these two guys were pretty similar in a many ways and they are just slightly different and those differences are where that additional torque comes from… those transfers make the difference. Those O series Stihl saw’s… the 026- 036…038 they were trying to create a Venturi effect… they wanted a tornado happening in the cylinder… ! We still want that but you don’t achieve that by blocking up your intake…it’s a combination of your exhaust port shape and your upper transfer shape…. Your new charge is spinning and your exhaust is pulling out from the opposite side and that’s what creates the swirling effect… Those intake’s need to have all that blockage removed because we’ve learned that we want an even intake. There’s an issue with those 026/36/38 because you have removed the blockage then you look at the intake boot and they have that same bad shape… there’s 300 series Husqvarna saw’s that have a rubber intake boot!!! 😉👍😂😂😂. You had these two saw’s almost head to head and 52mm bores over a 34mm stroke and then the boys at Husqvarna’s replaced the 272 with the 371-372 a 50mm over a 36mm stroke…
371 being a larger single ring and the 372 being the two smaller rings for the highest compression. I chose longevity over ultimate performance so I always revert my saw’s back into a 371 design with the one larger piston rig … the single ring piston stays cooler and there’s more lubrication and oil flowing around the cylinder walls with a single ring design. The 038 magnum definitely improves with a popup piston… This is definitely a great time to be into chainsaw engine building with all the new Hyway popup piston’s being offered today there’s a lot more piston swapping and upgrading that can be done by guy’s who don’t own a lathe… it’s also great to have these Hyway popup’s for blanks so you have less work to do to achieve your ultimate goal…. I don’t know what it is but having a Husqvarna piston in my Stihl saw or a Stihl piston in my Husqvarna saw is just a hoot for me!!! Swapping parts is great… I’ve never been super brand specific or brand loyal … and with the advent of increased aftermarket support… what you build is what you build! I was running around the junk yard at 8 or 9… by 11-12 I had an old Cadillac running… by about 14 the old codger who owned the junkyard was selling off my runner’s and flipping me cash to keep me working… and he made me a set of my own keys to all the equipment and buildings so I didn’t need to keep Hot-wiring the equipment to be able to get my work done! LMFFAO!!! It definitely beat the daylights out of collecting pop bottles and aluminum cans to earn my money!!! 😂😂😂😂. I was making a $100 dollar to get cars and trucks running! LMFFAO that was a whole bunch of money to me back then!
I wish I had a reason to cover up like that. Here in south Texas it’s shorts and tshirts everyday all year.
LOVED this vid..... Really GREAT content!
Good video Tinman.
Same as my 038 mag and 381..each has slightly different perfomance the way it cut the woods..i have them both for more than 10years..Sthil all the time..💪
I also look at the ring tension on each piston.
I wonder if flow could be visualized using smoke. Would the lower flow rate be representative of what's happening at high rpm?
Wow very interesting, good things to know
Hey hey Tinman. Have a good week buds. 🌳🌳🌲🌲✌
G'day Tinman, I have come across a number of instances where people have indicated that they had warmed over 038 that ran a single upper piston ring. I have built up a few of these saws now (wouldn't exactly called them "ported"...) but have yet to try one with a single piston ring.
Tinman I have a stihl 038 magnum and it came from the factory with a single ring on the piston and I know it's never been messed with because I am the only owner. I messed with the exhaust opened it up a little bit. Can I do anything else to it without porting. This saw was made in Brazil. The main thing I hate about this saw is the intake filter. Something for you to think about is can you put a 041 or 046 piston and cylinder on a 038 mag so you could have a cold air filter,different carb and cover. This is something I have been thinking on for a while but don't have the money or knoledge. Thanks for your videos keep up the good work from South Carolina
My favorite saw is the 272 with a 20inch Oregon Versalite bar.
Good points buddy, first build/transformation was a turd saw 029, bb and what I could do to it being clambshell, to 039....good good power but with a 25 heavy bar...man it's a lot for what it is, got to pull out my big nasty fun saw 372xp BB ported and pipes 28 sugi full house, big hard pecan, tree, guy beside me with a 271 just stopped after 1 cut I'd dun made like 6 with no effort lol, I love that saw, i cant put big or enough weight on her to bog her...major torque finally balanced the hp with it but still insane torque, 550 starter rope cord..have to
Air has mass, ramping up an opening allows it to start moving, winding it like a rubber band. That applies to exhaust primarily but also intake. Exhaust exiting can help pull air through the intakes.
Turbines, air/fluid are often contoured to permit the flow.
I've always wondered about the crankshift between the two as in weight
Nice content!
The .038 intake is aiming to swirl the air. It might be to make sure bearings are lubed, and the fuel stays at the outside near the transfers.
The 038 intake nub is like an inverted walker piston notch which is supposed to ramp the intake flow.
Something to think about over dinner.
The crank whipping around at 10k rpm will swirl any charge going in.
The fuel air charge doesnt go across it goes down into the crankcase then gets pushed up through the piston windows.
Airflow, something that a lot of folks don't really think about, but some professions, it's thing that matters. Are the cylinders close enough that one could bolt a 272 cylinder on an 038 or vice versa? I know there is a lot more involved like carbs, etc but that to me would be an interesting way of comparing.
What length bar do you use on the 272
Thanks Tinman
What if you take a different intake Boot from another stihl on the 038?
it would be intrest,ing test with different weigt of piston how the saw runs
Is there any difference between the 038 and the 381 other than a decomp???
My 266xp from 1990 has 220 psi for compression is this Normal?
Have you done much work with the new G660 Pro version of the Holzfforma saws??? I just picked one up and I'm debating weather I should have it ported or just run it out of the box. It's going to be my big wood saw so I wouldn't mind freeing up some extra low end torque if possible. Not looking for a hot rod, just a little more grunt than OEM. I plan on running it until the original top end takes a crap, partially to see if they are full of crap about having a better piston and rings... plug I'd like to see how it runs with a pop up big bore top end eventually, but first I want to experiment with it with all it's OEM parts for a little while, at least long enough to get an idea if these are actually worth the extra money compared to the base model g660.
What are your thoughts on the subject TinMan???
Very good. If you had time and patience a new purpose made manifold boot and a different carb maybe the 038 would be cool to see.
Hey Tinman
Will a husky 266 clutch cover and brake assembly work on a jonsered 630.
It will go on, however you will need to trim the back corner of because the wrap handle sits in a different location on the red saws than orange ones.
Do they both have the same stoke ?
This reminds me of comparing a KTM 250SX top end to a YZ250
There are many locals who swear by a 266, but I couldn't sell them a 268 or 272 if my life depended on it. 266's have a much smaller chamber than the later saws.
Whats the difference in rod ratio?
could you leave one ring off on the 038?
nice interesting video ,probably gonna have to watch again to embed the info ha ha
Can't wait to see you mod these two saws and do a side by side, if that's what you choose to do. 🍿🍿🍿
Tinman do you have any theories on why stihl designed the intake tract in such an odd pattern, their must be some logic behind it?
Cool video. I’ve never run an 038 but my 028 super has way more pull than my 026 for almost the same CCs. I usually just run the 026 though because it’s quite a bit lighter and cuts about as fast unless you’re getting into 12”+ wood.
2000 rpm does some good. My 346xp will cut 16” hard wood faster the a friends 2071 if I keep the rpm up. It tweaks him every time. He will lift a log with his excavator and I get 6 pieces of firewood before he gets 5, then he changes chains or bars and repeat. I have to keep it on screech. I also have a 290, it’s a heavy equivalent to the 346, it has more grunt but less screech.
Your 028 Super is a bigger saw than the 026. The 026 is 48cc, the 028 Super is 51.5cc.
Ported the 026 more than catches up to the 028.
@@82f100swb True an 028S is few more CCs but it has way more bottom end than an 026, very torquey old saws for their displacement. It is also pretty heavy for its CCs so I usually just grab the 034 or my ported 272 for bigger stuff. This summer I think I’ll port an 026 because like you said, I know it would smoke a stock 028S and make an awesome little saw for most smaller stuff 👍
@@rydplrs71 Yep the little saws sure can cut good with a sharp chain and set rakers. Can’t dog in quite like the bigger saws but if you just let them eat they can do great.
@@rileyjohnston8393 The 026 actually has a 1mm longer stroke than the 028. I have a super and wood boss on the shelf, but it's hard to want to run them. If you poke through my videos on here there's a few of my 026. It's significantly faster with 3/8 than .325 now.
Tinman. Look into conrod crank ratio. It makes a difference at what rpms the best power is produced. Two saws with the exact same port timings and spark timing and same cc, will perform at different rpms. Higher rod ratio better for higher rpms. Lower rod ratio better for lower rpm.
I’ve have both and my 272 will cut circles around my 38, and no I’m not a husky fan boy, I like both of the saws that’s why I have both
If the 272 piston would work in the 038 I'd give it a go in mine, how do they match up in terms of the piston skirt sizes and orientation related to the various openings in the cylinder?
That would be interesting.
The 272 piston is taller by a large amount. It would not be a direct swap by any means.
Tillotson he19a carb is a good replacement for the bing
How about Zama brands?
Is it ridiculous the thought of removing one ring from piston and returning it to the cylinder with only one? What would happened?
I run dual ring saws single ring quite often, usually after I've removed the support for that lower ring.
@@82f100swb interesting
@@82f100swb do you run the top or bottom ring? thanks for the info!
@@will47331 Just the top. Usually it's the lower that gets in my way at the intake port.
👍
Can you run only 1 piston ring on a 2 ring piston for less drag? And thank you for all the time you spend teaching us! great guy!!!
Yes you can run 1 ring.
Everybody forgets the air intake and filtration. The 272 is fantastic, the 038 is not.
O38 all the way
aim thinking here little bit heavyer pistong makes more tork. a can be wrong too.
Tin man id weight that 038 piston. Then I'd grind the casting seams out of it and then chamfer the skirt hard like 1/4" . dime round the skirt corners and then bake the piston and weight it again and run it
Why ? .... More AIR = More TORQUE, keep repeating this simple law of physics until it sinks in! Of course there are those who will say it’s not a “ported saw” UNLESS it’s had machine work done to it , complete and utter rubbish !