It would have been interesting to provide a short history on the X-Torq, in so much that Husqvarna purchased Zenoah of Japan to acquire their "strato-charged" engine design patents and rebranded it as the X-Torq. AND, RedMax is the US subsidiary of Zenoah which was established in 1987. AND, Husqvarna AB-Sweden Group acquired Zenoah/RedMax in 2007.
Thanks for the thorough explanation! It's videos like these that help rookies like myself. Never feel like you're rambling I always get something good out of these types of videos.
I can keep up and understand, but it's tough. Now then for me, to explain simple one type porting to someone else, would be almost impossible. This info. is more than basic,which is what i like.
Thank you so much. Have been running chainsaws since 1966. Didn't know the difference in saws but have only owned pro saws. Mac saws were my love. Still have a 10 10 pro, 700 pro , pro Mac 5, and a mini Mac. They still are used and run,but have Stihl, and Husqvarna pro saws that are the runners. ~y sons rebuild and keep us running. You have helped me keep from being ignorant
Thanks for making these videos! You've inspired me to build some of these hutzl saws and I'm super enjoying it! These aftermarket parts make it possible for me to learn so much more. Thanks
Good video. I look at it like this. If the side of the piston is used for one side of the transfer ports, it's an open port cylinder. If not it's a closed port cylinder. Cheers Willy
Thanks for your sharing of informations. I like a lot chainsaws and i haverá partner 550 and because your proud in salvage 50 -53 c Huskies and johnsered i Stay with my first saw. i cleaned it to shine estate and put new selas,and i dril the mufler restritor in mufler entrance and Ported exaust Port without opened piston side only wall to enlarge mufler side.With verá clean air filter,razor hand filling h42 and wow how it cut!with 17" bar cuting very Dry pines or eucaliptus and riping.That partner 550 have grunt to firewood cuting.And is true a open Port with single ring helps to High rpm but in low rpm is slower than closeports. I tarde good Shake 372 xp, two 372 x torq,one 576 xp no at,stihl 362 cm and with a 850 dólares profissional. You have right this Tipe of OpenPort is no problem if we clean it and put it in good Shape. One more time thanks.Stay please posting I Will drink it and try to make it the sabe way. Greatings from oporto Portugal André Campos.
Just love your vids, so much information and they are really helpful. If you have te time to make some vids about the basics of porting and modifying chainsaws i would really appreciate that. Also something about the special tools and such I would really like to get in to this sort of stuff. Right now i have a couple of stihls but I also would like to get in to huskys. Thanks
Hey Afleetcommand, the cylinder that you are holding at 2.03 looks identical to the one on my 350. I was wondering if you can cut out the groove in the transfer ports for more air flow or if they are needed for piston ring support? Thanks
Well said. I do have a question about modifying a stock saw. Does the increase in performance reduce the life of the engine or the reliability and what modifications have you experienced displayed this if any. Walt do you have a list of do's and don't mods you have learnt from over the years. Great topic and look forward to more. Take care.
+STEVE ROB That is one of those depends questions. Common sense will tell you increasing compression, heat, moving the power band up, etc. will stress the bottom end but if the bearings are still with in their design parameters, the actual impact will be minimal. And things like muffler mods where you are getting the heat out can actually help service life. So yes those builds that push design parameters with RPM's and/or Compression (heat) can reduce the life some.
Can a squish band be too narrow ? I have an original Stihl 028 WB type 1 ( 44 mm bore ) whose squish band is only about 2 mm wide, as compared to the later models that have about an 8mm band. When did Stihl switch to the T27 cap screws, (my 028 is put together with hex-head cap screws, (It's all original, my father was the first owner, purchased in the very early 80s) Thanks for the video
yes it can, obviously you don't want the piston to hit the squish band. The numbers I use to be safe is .020". I have pushed the limit a bit to .015 but that was also with a "machined" squish band and other things were in play. But for a work saw the .020" is a good number. I think we over analyze often when building these little motors. Most aren't going to earn money racing other saw. And most are used by a person "solo" so getting the job done with no hassle and reliably is more important than a few percentage points more power.
@@afleetcommand I mis-stated the question, sorry. not the squish between the piston and band, but the width of the band from the cylinder wall to the center,, , basically the old cylinder has almost no squish band at all, , , ,thank you for answering, The squish was 48 thousandths, I did a gasket delete, and that brought it to 0.025, that is where I think I'll leave it. it runs fine, but i still have to blow out the tank, and put in a layer of RedKote to seal it, so as of now, it runs better than it did, but I still might need to change some of the ports to compensate for lowering the jug. You guys really turned me onto to Husqvarnas and Jonsereds, especially the Red 2071, Thank you.
Actually a lot of the early saws had that "dome" style combustion chamber. AND not surprisingly the trend to cut into the squish band to reduce the size of the combustion chamber was the result. Problem is the "flow" of the fuel mixture from the outer part of the cylinder diameter to the area in the combustion chamber is a place gains can be had and with the "dome" pistons they had to be cut to match the changes. Want the resulting shape to promote the flow of the gas air mix into the combustion chamber...a subject in itself
@@afleetcommand yes, thank you again. When I looked at the configuration, I thought about taking some meat off of the bottom of the jug, and cutting a ring from the top of the piston to compensate for the reduced height, but decided not to do anything further than gasket delete. Reason being, I don't want to start opening the top of the exhaust, and secondly, I was concerned that it would yield too much intake duration. I am going for easy to start, and more torque anyway. If I need a faster chain, an 8 point sprocket can be used. Other than a delete, , , the only other thing I did, was to break the glaze on the cylinder, and put on new rings. the saw was almost never used, and I am trying to keep it original as possible. I have a ton of other stuff on the bench to play with, ,, and the next purchase/build will be a Jonsered, or Husky...Many thanks for this and all of your videos, you guys are great.
to both questions. 550 is a completely different design, a 50 vs. 62 cc saw. If you had miss typed and meant 555, the answer would be yes and no. So no
I ported my 400 cc 2 stroke recently. This just my first one. Lost some low end but got alot more mid range. Just need a pipe to compliment the porting. I oval bored my carb and got some gains all around going 1mm larger, but lost low end and top going 2mm larger. Obviously I did not have enough port to warrant going 2 mm. However, the new pipe may allow the engine to grow into the carb, dunno. The stock pipe is highly inefficient in its design in my motor.
Uhhhh... A+++ and all, big Likes, but wish you'd put TRANSFERS in the title, dude this is the best/most comprehensive "transfers-comparison" video I've come across, by a pretty large margin actually, have been literally collecting pics (usually screenshots) of various jugs' transfers, because it just blows my mind how much variance there is here I mean the rest of the jug is basically the same as 30yrs ago but transfers wow have they changed, the echo 7310 that has one of the uppers split to 2 windows (for 3 total up top) because it's so wide. Would you say that MIXING transfer charge, and the exhaust gas, is desirable/the goal? I keep hearing how you want to "have exhaust escape, pushed-out by the incoming transfer charge" but people advocate you aim those upper transfers laterally, that seems like a good way to intermix with exhaust gas, I would've liked to say "upwards would help" but the up-swinging piston should be all the "up" that charge needs, am thinking that when people do uppers aimed "backwards and laterally", the lateral part is pointless/of no use, it's only the aim backwards away-from the exhaust port that is of value in transfer-direction (ie, "up/down" is almost an irrelevant plane of action, insofar as transfer direction/aim, because of the piston movement)
Would also love elaboration on the idea that Husqvarna has literally hobbled saws via transfer-sabotage as you describe it, for reasons of price-points (I mean, you can open those transfers, working them is so easy, it'd be like using a very restrictive muffler-deflector plate that could just be un-screwed :P Maybe an extreme analogy but should make the point! Would expect a more 'uniform' downgrading through the cylinder, than a single-point weakness (there must be some secondary benefit to the larger transfers if they really are doing it that way, IE could it be that squeezing the transfers up's the power but down's the fuel-efficiency? This wouldn't be 'price point' so much as 'power point' if that makes sense!) Thanks for posting all this awesome content, and nix to any thoughts like you expressed Re you 'needing' to do more basic stuff, there's plenty of folk doing that, you're specialized we need you on the cutting edge stuff, stay on transfers not on basics ;D
Tried to keep it simple :) Now retired I have more time. Prolly should do a update and "2.0" , especially as most saws now have some derivative of these heat "charged" ( Like 550-572 ) style transfers and or strato ports. Especially the new eco saws using heat to expand/accelerate the charge into the combustion chamber go against conventional thinking in the chainsaw community....why so many who "mod" them miss the mark :)
Husqvarna did, 545,555,565, 365 etc. And I would change the description to modify powerbands by changing port size....and that might be a price point driven design but also there may be more to it. For example my 565 has the same basic top end as a 572, but doesn't have the rpm's or top end snap. BUT has a wider mellow power band that starts pulling real hard at a lower RPM than the 572....and in my humble opinion is easier to use , especially with the long bars in awkward positions. I guess the concept "more isn't always better" in both transfer x-sectional area and in peak power. The 565 is proof to me that just like in the 1980's when dyno's showing peak HP on motocross race bike missed it, the same is happening now in the saw community 40 years later ...its about matching power & power delivery to a persons world. And right now a 565 is better for me than the more of everything 572's. ( I have both )
My first thought on the new port design was, 1) using fuel to regulate temps; and or 2) use heat to boost temp of fuel for, more complete combustion; 3) lower Nox"s..pollution.
Theyre vaprizeing the fuel for a more burnable mixture . Same thing could be done with more power if the carb produced smaller droplets . Or if you could break them up afterwards .
I just got three aftermarket kits for the 346xp's ... They're what like 44.3 diameter ... The stock is 44 or 45 mm on a 350's ... What was your findings on the results of throwing these open port 346's jug and plugs on the 350's... About the same power? Or slightly better power at the top end of the RPM range? Thanks Walt!
+David Thorne Typically a 346 will run to 14300 and make more power when twisting at the higher RPM's, You can "port" or tweak a 45mm 350 with the caps to match a 346 quite easily and it has a power band at a low set of RPM's. Never used AM 346 top ends, and now the cost of OEM's is around 75 dollars. Kind of took away some of the luster for the AM top end kits for me.
+David Thorne If they are AM open port top ends, I doubt they will run as well as the OEM 346 or 353 top ends. BUT I never tried! So that is pure speculation,
I go onto the www.hlsproparts.com to check the deals of the day stuff and these kits were like $20 bucks apiece. So, I had to grab a few...just to see...right! They look good and I have them rubbed down with my Amsoil engine builders lube... So, I'm hopeing to get some time over the next few weeks to have one to compare. I love those Hutzl kits for the 45mm big bore for the 350 with the transfer port caps that come off... To make cleaning up easier.. And being $35 bucks to get a 350 running means I really like those.
thanks for all knowledge you share.The husky four ports design is 5*****. I now suspected my 2013 372Xt will not be a true upgrad of my 2010 xp, because the pre x torq design( two passages for air). In your opinion the Xt is better or only born for Epa regulations and was better i stay with my first Xp? The old xp has 4.3N at 6600 or Xt 3.8 at 8100 that say XTtork is better at full trotle and have better chain speed at the tree than the xp? I will port my xt and not sell the xp. Please help me to make a correct view. My two saws for now stay original because i only cut a tone a year and i´m adited to good saws. Thanks for your help. André Campos
+andré Campos XT is an EPA driven design. They have done a great job in keeping within EPA mandated parameters while producing a saw that about matches an old style 372. I would build to the original design.
How do you build your chainsaw engines for torque vs. horsepower? The Stihl 051 and many McCulloch chainsaws were saws you could "lug" through a big hard chunk of Red Oak or Red Elm. How do these saws (Stihl 051/056 and McCulloch "10-series" generation like the 10-10, 55, 60, 7-10/700, SP 81) compare to a Jonsereds 2166/Husqvarna 365 & 2172/372? What made and still makes the McCulloch Super Pro 125 such a beast?! Torque vs. horsepower comparisons really, I mean really interest me when you're cutting wood.
+John Lincicum I shoot for torque on my builds, higher compression, a littler later to open the exhaust, and stuff like that. I'm more interested in a saw that won't fall on its face if it gets out of its sweet spot than one that sounds like a dentist drill. Those old mac's compare favorably to the "200" series like the 266 and 272 but the 300 series just have more of everything power wise in a lighter package. Although the sp81 is a beast of a saw!
+afleetcommand I love the SP81! Ours is of course a full wrap handle bar too. We have a 28" bar on it. I have all the McCulloch saws listed except the Super Pro 125. The Jonsereds 2166 isn't in my hands yet. Making payments (2), first payment today, partly because of money and partly because the dealer had hip replacement surgery! Last payment is next month. I would like to compare the 700 to the 2166, even if it is slower, just to see how much. But the 2166 has a 24" bar and the 700 has a 20" bar. Will the bars fit from one to the other? I just used the 700 Tuesday, man what a nice saw when it runs right! I just got it back. Darn ethanol gas in the farming/rust belt, I've been trying to avoid it like the plague! I only use gas from 2 gas stations now, 1 is 93 octane with 10% and is 3 miles outside of my town and just recently I found a gas station in Wisconsin on my way to work that has no ethanol 91 octane.
It makes sense if you think about what fuel you're burning. They keep the oil gas mix cool and mixed to lubricate the bottom end and keep the heat down on the crank and bearings. Then they give it a run across a heated port just before combustion thus aiding the desired process. This will give it a cleaner more effective burn yet still effectively lubricate the top side. When fuel warms up it atomizes into a vapor which we all know is the most efficient way to ignite it and utilize it to send that piston back down..
They could probably use a capacitor or several capicitors in parellel instead of a battery for fuel injection. My 241 will crank in one pull if it is nice and warm outside. My 261 will not. It usually takes about 4 to 5 pulls to get it running. I have never had an auto tune saw, so I have no experience with those saws. My 241 did crank on one pull in a snow storm this winter, but I did have it in the house before I took it outside, but it was below freezing, outside.
Every new engine design is a compromise, usually predicated by folks in the finance department. The head of PR at Remington Arms once told me that changes to their products were not made by the engineering department but the bean counters, which is why known problems usually never got fixed. Build it cheaper, with more PR jargon and some idiot will still buy it and in today's world make the cost of replacement parts as expensive as possible and the units, themselves, basically unserviceable. Then, they can sell you, hopefully, another unit at an even higher price. Look at the new Briggs lawn,power engines - you never have to change the oil; just add new oil to keep it filled. Right!!
True, I started to get into the physics is a recent video. The saw community isn't really ready for true math & science. Still caught up in the black magic, bling, and entertainment as demonstrated with a lot of the really popular & large channels. I remember the same in the 1970's racing 125's.... then along came pro circuit & Yoshimura and a few other true engineering houses. Once the saw community gets past that, I'll drop in some math maybe :)
Just wait until they can find a way to have a battery in a saw, so they can make saws fuel injected with a computer controlling everything. Mtronic and auto tune are just the first generation of their plans for our future. With the Xtorq it is just like we were with vehicles in the 1970's. Remember the air pump we had on those vehicles? They consistently caused detonation due to a lean mix. Can you imagine what detonation would do to a two cycle engine? I just do not understand why they lean on the outdoor power equipment flks and let te real polutors get a pass -18 wheelers. OPE consitutes less than 1% of the overall pollution.
It would have been interesting to provide a short history on the X-Torq, in so much that Husqvarna purchased Zenoah of Japan to acquire their "strato-charged" engine design patents and rebranded it as the X-Torq. AND, RedMax is the US subsidiary of Zenoah which was established in 1987. AND, Husqvarna AB-Sweden Group acquired Zenoah/RedMax in 2007.
Thanks for the thorough explanation! It's videos like these that help rookies like myself. Never feel like you're rambling I always get something good out of these types of videos.
I can keep up and understand, but it's tough. Now then for me, to explain simple one type porting to someone else, would be almost impossible. This info. is more than basic,which is what i like.
Thank you so much. Have been running chainsaws since 1966. Didn't know the difference in saws but have only owned pro saws. Mac saws were my love. Still have a 10 10 pro, 700 pro , pro Mac 5, and a mini Mac. They still are used and run,but have Stihl, and Husqvarna pro saws that are the runners. ~y sons rebuild and keep us running. You have helped me keep from being ignorant
Peter, you’re quite a guy! 👍
Obscure video with very few views, but SPOT ON! Thanks! Wish I could give you more than one "thumbs up"!
Thanks for making these videos! You've inspired me to build some of these hutzl saws and I'm super enjoying it! These aftermarket parts make it possible for me to learn so much more. Thanks
Good video. I look at it like this. If the side of the piston is used for one side of the transfer ports, it's an open port cylinder. If not it's a closed port cylinder.
Cheers
Willy
Yet another outstanding video! This is great information!
New and interesting stuff to me. Thanks for sharing your hard earned knowledge!
Thanks for your sharing of informations.
I like a lot chainsaws and i haverá partner 550 and because your proud in salvage 50 -53 c Huskies and johnsered i Stay with my first saw.
i cleaned it to shine estate and put new selas,and i dril the mufler restritor in mufler entrance and Ported exaust Port without opened piston side only wall to enlarge mufler side.With verá clean air filter,razor hand filling h42 and wow how it cut!with 17" bar cuting very Dry pines or eucaliptus and riping.That partner 550 have grunt to firewood cuting.And is true a open Port with single ring helps to High rpm but in low rpm is slower than closeports.
I tarde good Shake 372 xp, two 372 x torq,one 576 xp no at,stihl 362 cm and with a 850 dólares profissional.
You have right this Tipe of OpenPort is no problem if we clean it and put it in good Shape.
One more time thanks.Stay please posting I Will drink it and try to make it the sabe way.
Greatings from oporto Portugal André Campos.
Thank you fleet, very informative. Answers a lot of my interests .
OUTSTANDING VIDEO! I’ve learned so very much from your videos. Thank you!
Just love your vids, so much information and they are really helpful.
If you have te time to make some vids about the basics of porting and modifying chainsaws i would really appreciate that. Also something about the special tools and such I would really like to get in to this sort of stuff.
Right now i have a couple of stihls but I also would like to get in to huskys.
Thanks
Excellent VIDEO. Could you please go through step by step how to modify a makita ea7900? Thank you.
Thank you for being a benevolent person.In my day ,you had to figure it out on your own.
Thank you!Very informative info for a (somewhat)noob like me.Awesome!
Hey Afleetcommand, the cylinder that you are holding at 2.03 looks identical to the one on my 350. I was wondering if you can cut out the groove in the transfer ports for more air flow or if they are needed for piston ring support? Thanks
Never tried so really can't answer that with authority. Buy an AM cylinder and try it..:)
Well said. I do have a question about modifying a stock saw. Does the increase in performance reduce the life of the engine or the reliability and what modifications have you experienced displayed this if any. Walt do you have a list of do's and don't mods you have learnt from over the years. Great topic and look forward to more. Take care.
+STEVE ROB That is one of those depends questions. Common sense will tell you increasing compression, heat, moving the power band up, etc. will stress the bottom end but if the bearings are still with in their design parameters, the actual impact will be minimal. And things like muffler mods where you are getting the heat out can actually help service life. So yes those builds that push design parameters with RPM's and/or Compression (heat) can reduce the life some.
Can a squish band be too narrow ? I have an original Stihl 028 WB type 1 ( 44 mm bore ) whose squish band is only about 2 mm wide, as compared to the later models that have about an 8mm band. When did Stihl switch to the T27 cap screws, (my 028 is put together with hex-head cap screws, (It's all original, my father was the first owner, purchased in the very early 80s) Thanks for the video
yes it can, obviously you don't want the piston to hit the squish band. The numbers I use to be safe is .020". I have pushed the limit a bit to .015 but that was also with a "machined" squish band and other things were in play. But for a work saw the .020" is a good number. I think we over analyze often when building these little motors. Most aren't going to earn money racing other saw. And most are used by a person "solo" so getting the job done with no hassle and reliably is more important than a few percentage points more power.
@@afleetcommand I mis-stated the question, sorry. not the squish between the piston and band, but the width of the band from the cylinder wall to the center,, , basically the old cylinder has almost no squish band at all, , , ,thank you for answering, The squish was 48 thousandths, I did a gasket delete, and that brought it to 0.025, that is where I think I'll leave it. it runs fine, but i still have to blow out the tank, and put in a layer of RedKote to seal it, so as of now, it runs better than it did, but I still might need to change some of the ports to compensate for lowering the jug. You guys really turned me onto to Husqvarnas and Jonsereds, especially the Red 2071, Thank you.
Actually a lot of the early saws had that "dome" style combustion chamber. AND not surprisingly the trend to cut into the squish band to reduce the size of the combustion chamber was the result. Problem is the "flow" of the fuel mixture from the outer part of the cylinder diameter to the area in the combustion chamber is a place gains can be had and with the "dome" pistons they had to be cut to match the changes. Want the resulting shape to promote the flow of the gas air mix into the combustion chamber...a subject in itself
@@afleetcommand yes, thank you again. When I looked at the configuration, I thought about taking some meat off of the bottom of the jug, and cutting a ring from the top of the piston to compensate for the reduced height, but decided not to do anything further than gasket delete. Reason being, I don't want to start opening the top of the exhaust, and secondly, I was concerned that it would yield too much intake duration. I am going for easy to start, and more torque anyway. If I need a faster chain, an 8 point sprocket can be used. Other than a delete, , , the only other thing I did, was to break the glaze on the cylinder, and put on new rings. the saw was almost never used, and I am trying to keep it original as possible. I have a ton of other stuff on the bench to play with, ,, and the next purchase/build will be a Jonsered, or Husky...Many thanks for this and all of your videos, you guys are great.
can I replace the caps on the cylinder of my 550 with those of a 562, for more power? or does that cause problems with the autotune?
no
@@afleetcommand is the answer no to the question whether I can replace the caps
to both questions. 550 is a completely different design, a 50 vs. 62 cc saw. If you had miss typed and meant 555, the answer would be yes and no. So no
I ported my 400 cc 2 stroke recently. This just my first one. Lost some low end but got alot more mid range. Just need a pipe to compliment the porting. I oval bored my carb and got some gains all around going 1mm larger, but lost low end and top going 2mm larger. Obviously I did not have enough port to warrant going 2 mm. However, the new pipe may allow the engine to grow into the carb, dunno. The stock pipe is highly inefficient in its design in my motor.
Sounds like your chasing your tail. That's what happens.
Uhhhh... A+++ and all, big Likes, but wish you'd put TRANSFERS in the title, dude this is the best/most comprehensive "transfers-comparison" video I've come across, by a pretty large margin actually, have been literally collecting pics (usually screenshots) of various jugs' transfers, because it just blows my mind how much variance there is here I mean the rest of the jug is basically the same as 30yrs ago but transfers wow have they changed, the echo 7310 that has one of the uppers split to 2 windows (for 3 total up top) because it's so wide.
Would you say that MIXING transfer charge, and the exhaust gas, is desirable/the goal? I keep hearing how you want to "have exhaust escape, pushed-out by the incoming transfer charge" but people advocate you aim those upper transfers laterally, that seems like a good way to intermix with exhaust gas, I would've liked to say "upwards would help" but the up-swinging piston should be all the "up" that charge needs, am thinking that when people do uppers aimed "backwards and laterally", the lateral part is pointless/of no use, it's only the aim backwards away-from the exhaust port that is of value in transfer-direction (ie, "up/down" is almost an irrelevant plane of action, insofar as transfer direction/aim, because of the piston movement)
Would also love elaboration on the idea that Husqvarna has literally hobbled saws via transfer-sabotage as you describe it, for reasons of price-points (I mean, you can open those transfers, working them is so easy, it'd be like using a very restrictive muffler-deflector plate that could just be un-screwed :P Maybe an extreme analogy but should make the point! Would expect a more 'uniform' downgrading through the cylinder, than a single-point weakness (there must be some secondary benefit to the larger transfers if they really are doing it that way, IE could it be that squeezing the transfers up's the power but down's the fuel-efficiency? This wouldn't be 'price point' so much as 'power point' if that makes sense!)
Thanks for posting all this awesome content, and nix to any thoughts like you expressed Re you 'needing' to do more basic stuff, there's plenty of folk doing that, you're specialized we need you on the cutting edge stuff, stay on transfers not on basics ;D
Tried to keep it simple :) Now retired I have more time. Prolly should do a update and "2.0" , especially as most saws now have some derivative of these heat "charged" ( Like 550-572 ) style transfers and or strato ports. Especially the new eco saws using heat to expand/accelerate the charge into the combustion chamber go against conventional thinking in the chainsaw community....why so many who "mod" them miss the mark :)
Husqvarna did, 545,555,565, 365 etc. And I would change the description to modify powerbands by changing port size....and that might be a price point driven design but also there may be more to it. For example my 565 has the same basic top end as a 572, but doesn't have the rpm's or top end snap. BUT has a wider mellow power band that starts pulling real hard at a lower RPM than the 572....and in my humble opinion is easier to use , especially with the long bars in awkward positions. I guess the concept "more isn't always better" in both transfer x-sectional area and in peak power. The 565 is proof to me that just like in the 1980's when dyno's showing peak HP on motocross race bike missed it, the same is happening now in the saw community 40 years later ...its about matching power & power delivery to a persons world. And right now a 565 is better for me than the more of everything 572's. ( I have both )
@@afleetcommand Friend, or +500 turnover from the maximum permissible damaged saw?
what power is the scythe 244rx?
Cool great video I am a stihl mec and I am going to get a saw and port it and mod it that was some great info thank you
I learned a lot thanks for making the video!
My first thought on the new port design was, 1) using fuel to regulate temps; and or 2) use heat to boost temp of fuel for, more complete combustion; 3) lower Nox"s..pollution.
Theyre vaprizeing the fuel for a more burnable mixture . Same thing could be done with more power if the carb produced smaller droplets . Or if you could break them up afterwards .
I just got three aftermarket kits for the 346xp's ... They're what like 44.3 diameter ... The stock is 44 or 45 mm on a 350's ... What was your findings on the results of throwing these open port 346's jug and plugs on the 350's... About the same power? Or slightly better power at the top end of the RPM range? Thanks Walt!
+David Thorne Typically a 346 will run to 14300 and make more power when twisting at the higher RPM's, You can "port" or tweak a 45mm 350 with the caps to match a 346 quite easily and it has a power band at a low set of RPM's. Never used AM 346 top ends, and now the cost of OEM's is around 75 dollars. Kind of took away some of the luster for the AM top end kits for me.
+David Thorne If they are AM open port top ends, I doubt they will run as well as the OEM 346 or 353 top ends. BUT I never tried! So that is pure speculation,
I go onto the www.hlsproparts.com to check the deals of the day stuff and these kits were like $20 bucks apiece. So, I had to grab a few...just to see...right! They look good and I have them rubbed down with my Amsoil engine builders lube... So, I'm hopeing to get some time over the next few weeks to have one to compare. I love those Hutzl kits for the 45mm big bore for the 350 with the transfer port caps that come off... To make cleaning up easier.. And being $35 bucks to get a 350 running means I really like those.
I did one with the 45mm Huztl that did in fact come out pretty well.
thanks for all knowledge you share.The husky four ports design is 5*****. I now suspected my 2013 372Xt will not be a true upgrad of my 2010 xp, because the pre x torq design( two passages for air).
In your opinion the Xt is better or only born for Epa regulations and was better i stay with my first Xp?
The old xp has 4.3N at 6600 or Xt 3.8 at 8100 that say XTtork is better at full trotle and have better chain speed at the tree than the xp?
I will port my xt and not sell the xp.
Please help me to make a correct view.
My two saws for now stay original because i only cut a tone a year and i´m adited to good saws.
Thanks for your help.
André Campos
+andré Campos XT is an EPA driven design. They have done a great job in keeping within EPA mandated parameters while producing a saw that about matches an old style 372. I would build to the original design.
thanks!
I would sell my xp.
greetings
André Campos
How do you build your chainsaw engines for torque vs. horsepower? The Stihl 051 and many McCulloch chainsaws were saws you could "lug" through a big hard chunk of Red Oak or Red Elm. How do these saws (Stihl 051/056 and McCulloch "10-series" generation like the 10-10, 55, 60, 7-10/700, SP 81) compare to a Jonsereds 2166/Husqvarna 365 & 2172/372? What made and still makes the McCulloch Super Pro 125 such a beast?! Torque vs. horsepower comparisons really, I mean really interest me when you're cutting wood.
+John Lincicum I shoot for torque on my builds, higher compression, a littler later to open the exhaust, and stuff like that. I'm more interested in a saw that won't fall on its face if it gets out of its sweet spot than one that sounds like a dentist drill. Those old mac's compare favorably to the "200" series like the 266 and 272 but the 300 series just have more of everything power wise in a lighter package. Although the sp81 is a beast of a saw!
+afleetcommand I love the SP81! Ours is of course a full wrap handle bar too. We have a 28" bar on it. I have all the McCulloch saws listed except the Super Pro 125. The Jonsereds 2166 isn't in my hands yet. Making payments (2), first payment today, partly because of money and partly because the dealer had hip replacement surgery! Last payment is next month. I would like to compare the 700 to the 2166, even if it is slower, just to see how much. But the 2166 has a 24" bar and the 700 has a 20" bar. Will the bars fit from one to the other? I just used the 700 Tuesday, man what a nice saw when it runs right! I just got it back. Darn ethanol gas in the farming/rust belt, I've been trying to avoid it like the plague! I only use gas from 2 gas stations now, 1 is 93 octane with 10% and is 3 miles outside of my town and just recently I found a gas station in Wisconsin on my way to work that has no ethanol 91 octane.
is a mcculloch 10-10 considered a clam shell?
yes
@@afleetcommand what power is the scythe 244rx?
Thankyou.
hı ı need 52mm cylinder for dolmar 133
I wish I knew a 10th of what you do about these engines.
i dont like the design where the transfers go near the exhaust. a hot intake charge equals less power
That would be conventional logic...:) But are you sure?
It makes sense if you think about what fuel you're burning. They keep the oil gas mix cool and mixed to lubricate the bottom end and keep the heat down on the crank and bearings. Then they give it a run across a heated port just before combustion thus aiding the desired process. This will give it a cleaner more effective burn yet still effectively lubricate the top side. When fuel warms up it atomizes into a vapor which we all know is the most efficient way to ignite it and utilize it to send that piston back down..
Its well known the colder the intake charge the better
They could probably use a capacitor or several capicitors in parellel instead of a battery for fuel injection. My 241 will crank in one pull if it is nice and warm outside. My 261 will not. It usually takes about 4 to 5 pulls to get it running. I have never had an auto tune saw, so I have no experience with those saws. My 241 did crank on one pull in a snow storm this winter, but I did have it in the house before I took it outside, but it was below freezing, outside.
Every new engine design is a compromise, usually predicated by folks in the finance department. The head of PR at Remington Arms once told me that changes to their products were not made by the engineering department but the bean counters, which is why known problems usually never got fixed. Build it cheaper, with more PR jargon and some idiot will still buy it and in today's world make the cost of replacement parts as expensive as possible and the units, themselves, basically unserviceable. Then, they can sell you, hopefully, another unit at an even higher price. Look at the new Briggs lawn,power engines - you never have to change the oil; just add new oil to keep it filled. Right!!
Thank you !
Scavenging seems to be little talked about. The impact a muffler mod will make to back pressure etc
True, I started to get into the physics is a recent video. The saw community isn't really ready for true math & science. Still caught up in the black magic, bling, and entertainment as demonstrated with a lot of the really popular & large channels. I remember the same in the 1970's racing 125's.... then along came pro circuit & Yoshimura and a few other true engineering houses. Once the saw community gets past that, I'll drop in some math maybe :)
more detail needed
Just wait until they can find a way to have a battery in a saw, so they can make saws fuel injected with a computer controlling everything. Mtronic and auto tune are just the first generation of their plans for our future. With the Xtorq it is just like we were with vehicles in the 1970's. Remember the air pump we had on those vehicles? They consistently caused detonation due to a lean mix. Can you imagine what detonation would do to a two cycle engine?
I just do not understand why they lean on the outdoor power equipment flks and let te real polutors get a pass -18 wheelers. OPE consitutes less than 1% of the overall pollution.
The new autotune's draw power from the ignition module. Plenty of power for Fuel Injection to be had. Takes one revolution to get them going.
Friend, or +500 turnover from the maximum permissible damaged saw?
You need a camera man to zoom in on what you are explaining dude ...its hard to see exactly what you are trying to show your students.
not a teacher and certainly don't have any students :)