i have thought about this a lot; when i see 2 stroke motorbikes/snow machines and such, they always have a HUGE expansion chamber that takes in all the expelled gases and slowly funnels them out to a small outlet far from the (large) expansion portion. I have played around with this and one can either just straight shot the exhaust like 60s era saws, or copy the YZ80, CR 80 type expansion chamber that slowly funnel them to a small outlet. i believe that 2 strokes do not like immediate back pressure, they want time to have the spent gases to expand and draw gases slowly out. In a saw, i think the best would be to leave the large immediate expansion chamber and weld in a tapered outlet pipe.
Triaxial balance = there ain’t no free lunch! Generally speaking, the more power that you get from anything (except exhaust) the less life that you get from it. 100hp from a little Honda is doable at the expense of total lifetime. Exhaust is a different animal. Take headers on automotive for example. Longer engine life, more MPG’s, better fuel economy. People say that they are louder, well that depends on other things like what they selected for mufflers. Maybe more tinny but not louder note in and of itself. Tinnier only because of less thickness. I’m with you on everything that you’ve said here every since I’ve tuned in and subscribed. I don’t generally comment, but this one “sang” to me in a way that most people just don’t normally understand. Thank you Tinman for everything that you do and everything that you have done. I LIKE IT 👍 Just keep up your normal phenomenally good work. Excellent stuff my man.
Just got caught up on recent videos. The video on checking cylinder and cleaning the bore made me double back on reassembly of my echo cs302! Glad that was covered. Just finished restoring a 1952 Strunk 3-19. That project took 4 months and the saw I found out was built in my home town of Coatesville Pa. Thank you for all your help. Think I have a new sickness!!!
It's worth noting that more air equates to more fuel, which is more oil to the bearings. More power is better, until the heat becomes excessive... Typically good tuning makes for better distributed pressures on the crank and bearings. Finding efficiency is a fun game! Pipe sounds great!
One of the thing i like the most is that the muffler isn't sitting so close to the crank cases. The amount of heat sinking into the front of the case is huge especially when you are blocking up big logs and there isn't much air flow at the front of the saw. Plus, we all need more crack in our lives(not the drug kind). Cheers Tinman. That Harvey knows a thing or two.
I agree about the tuned pipe... If I'm gonna have that monstrosity on my saw, I want it to make substantial power. A turbo should give the back pressure I need...
I just built a muffler mod for my 372xp from one of the chinese aftermarket "high performance" mufflers with the side pipe exhaust. I cut out the factory exhaust pipe which was tiny, it would have been a close fit for a pencil... and opened up the hole and welded in a piece of 3/4 schedule 40 pipe(.680" ID) trying to keep as close to the 60-70% rule as I could with what I had on hand. This muffler has the baffle in it, but (looking from the back of the saw to the front as you're holding it) it has a huge port in the baffle at the bottom right corner to let the exhaust gas flow from the rear chamber of the muffler to the front chamber. I didn't alter any of the baffle. I made my exhaust outlet pipe long enough that it extends inside the muffler to about 3/4" from the left side of the muffler, and exhausts nearly straight out the right side, just in front of the chain brake handle. It has that "POP" in the exhaust, and sitting on the ground at idle, I can see it blowing saw chips around 3-5 feet away or more. It really flows the exhaust out, much better than I ever expected it would with the baffle in there. I don't know if it's making any more power, it kind of seems like it pulls harder now, but at least it isn't burning the crap out of my hand now when I'm buried in a long bucking it up like the OEM top port muffler did. That was the entire motivation for building the new muffler. What do you think about mufflers with the baffle in them? Would you leave it in there or take the muffler apart and remove the baffle? Is there anything I could do to increase the performance of this muffler? It does seem to be working good, the throttle response is nice and snappy, I'm happy with it so far in the 4-5 tanks of fuel I've ran through it. But if I can get a bit more out of it, I'm up to doing it
I have watched several chainsaw videos where they hollow out the mufflers and make the exit hole larger VS an untouched stock muffler and the modified mufflers always make more power as proven on a dyno
You can add a fairly large spacer where the gasket goes and increase the capacity of air the stock muffler holds which is a easy cheap way of adding a little air coushion kinda like an expansion chamber. I like what you do on your channel man. I've built old school saws for a long time. Mostly old steel body stuff but just ordered a new 550 xp to port and see what the new stuff is capable of lol. From what I'm seeing the new saws rip as is and with some port work should be little monsters.
2 strokes most definitely want an expansion chamber and a funnel to a small outlet. The size outlet determines the higher or lower... Rpm where the power is delivered. The larger expansion chamber gives a cushion of air and increases the usable power. Large expansion chambers are a must in high performance 2 strokes in my opinion. Look into dirt bikes, snowmobile, and mostly into gas powered rc cars and rc planes
I have 2 mac 10-10's and I wonder how a combo of both this style of pipe and the one you made for bucking would look/work. Awsome video and exceptional explanations as always Tinman!
With that design, it would be cool if you made the thicker tube longer, then welded a big nut on the end, with a big bolt on it, then you could have an adjustable length from the exhaust port to the flat end of the straight shot, where the sound/exhaust pulses bounce off, to see if you could get the exhaust gasses to keep intake charge in better, like a tuned pipe on a dirt bike. Can't remember what it's called, scavenging? Anyway, great channel, keep it up.
Just watched this video. Saw Ironhorse put this style pipe on a saw a couple of years ago. I built one for my Stihl 039, it works. Saw is much snappier. Stock and modded saw
That's a great question. 2 strokes need to scavenge some of the unburnt fuel and exhaust that is sent out of the exhaust port. So if you run one without a pipe then tend to lack power and run lean.
Good old CANADA 🇨🇦🇨🇦🇨🇦 it went from minus 32 to plus 3 in 24 hours here in ONTARIO crazy weather part of being 🇨🇦🇨🇦 French toast maple syrop and sausages lol don't forget bacon🥞🥞🥞🥞🥞😁😁😁😁✊✊✊ cold weather stay inside breakfast ,warm everyone's heart♥️♥️be safe everyone
I...personally mig or tig almost everything that small, but any welding or braizing process will work absolutely same end result if you know what ur doing, if ur good at braizing, whip out the torch, will be more than adequate
Braizing yields around 40sum thousand tensile strength standard welding is standard around 60 to 70 thousand for perspective do its way strong enough, I've made hydraulic fittings...mate how they shouldn't braizing many times and always holds also for dissimilar metals rather tig or torch brazing
Go to walmart, they sell 1/16 rods, for stick, fast hot flash tacks stacked together will work just fine and look like dimes, dont be afraid of the heat, high hea mean fast travel means less heat input, only thing with 8th is weight otherwise should be no diffrent really
I didn't know you were a road racing fan. I'm from Oklahoma and used to be a race bike technician for HSBK racing with P.J. Jacobson riding Moto America for us.
So many variants of building a pipe. Not for tin man necessarily but for the commenters. Hot air goes up cold air goes down. Might help others with building a pipe!
Hi Tinman my name is Tyler McLaughlin and I run a 272xp for cutting Cedar blocks currently having a small issue with getting my oiler to push enough oil and was wondering what is your favorite muffler say from Amazon ?
The single exit farmertec with enlarging the exit and shoving the pipe down at an angle to the corner and welding it in is a effective very easy and fast muff mode to make, blow that hole out bigger slipped bigger piece in a out 3/4 t 2 inches, burner in, roughly 5 min fix
Mr. Tinman my main saw is a stock 1984 Husqvarna 181 se would that size pipe be a good size? Or should I look for something slightly bigger in diameter.
That's a great saw and wicked pipe. How much to build me one Tinman. I'd love to try it out on my 268 stock. Let me know an I'm in. TC great content again. MahaloTinman🤙🤙🤙...Tdawg
I'm modding the muffler on my cs590 so should I gut the original and make 2 small pipes coming out out the front or put am single pipe coming out the side of the saw? Appreciate your response if you happen to answer. It's a new saw
People don't realize how much power it takes just to pump air through the engine. The parasitic losses from the flywheel fan, pumping air, and the chain are huge.
Had a friend who worked in a racing speed boat shop and they would spend days trimming pipes and sometime a whoops moment would come along and another set had to be built. The word extractor seems to fit the name for these builds. What does everyone think. Cheers everyone
nice pipe ! just finished my 262xp rebuild i see that the exhaust is not really great , the carbon just shoot on the cylinder when theres no screen on it. it will be hearthbreaking to sell this saw ! My first one
Tinman, have you ever experimented putting a pipe like this on the newer husky’s? Like your 562xp? I haven’t seen much out there other than a mod to the can.
i remember a honda hrc engineer saying they got over 200hp out of the honda nsr500 after spending months on pipe design. Then suzuki basically was allowed to darn near copy the nsr500 entire engine design.
The pipe is a nice design it's right up there with uncle Harvey's dual scrench pipe , but the best sounding chainsaw I ever heard was the old echo 650 evl , you knew what the saw was when you heard them running in the woods !
Man that saw sounds mean😂 best part about performance mufflers they sound amazing but they also make the saw preform ten times better. I like how there just not all noise it actually serves a purpose😎
A tuned pipe sucks! Lol Would the size of a stock muffler act like a chamber? Many you could make a pipe that works on 1/2-1/4 waves that would be smaller?
The second problem with the stock muffler is the port size is larger then the exit. It will create back pressure preventing the air pump from getting the bad air out.
Sound a lot quieter muffler to me and I hope it heats up where you at I live in the mountains in Northern California and we had over 4 ft of snow it’s slowly warming up hear bottom line I feel for you
I like my saws nice and warm, like holding a Ferrari in your hands. I built myself a 350 and it runs different than the others I have done. It doesn't have that pop/cackle at idle. I used a lot of epoxy in the engine to improve flow, so maybe that's why, I dunno. I think I'm going to try making one of those pipes and see what happens. It's just over 5hp right now.
i have thought about this a lot; when i see 2 stroke motorbikes/snow machines and such, they always have a HUGE expansion chamber that takes in all the expelled gases and slowly funnels them out to a small outlet far from the (large) expansion portion. I have played around with this and one can either just straight shot the exhaust like 60s era saws, or copy the YZ80, CR 80 type expansion chamber that slowly funnel them to a small outlet. i believe that 2 strokes do not like immediate back pressure, they want time to have the spent gases to expand and draw gases slowly out.
In a saw, i think the best would be to leave the large immediate expansion chamber and weld in a tapered outlet pipe.
Triaxial balance = there ain’t no free lunch!
Generally speaking, the more power that you get from anything (except exhaust) the less life that you get from it. 100hp from a little Honda is doable at the expense of total lifetime. Exhaust is a different animal. Take headers on automotive for example. Longer engine life, more MPG’s, better fuel economy. People say that they are louder, well that depends on other things like what they selected for mufflers. Maybe more tinny but not louder note in and of itself. Tinnier only because of less thickness. I’m with you on everything that you’ve said here every since I’ve tuned in and subscribed. I don’t generally comment, but this one “sang” to me in a way that most people just don’t normally understand.
Thank you Tinman for everything that you do and everything that you have done. I LIKE IT 👍 Just keep up your normal phenomenally good work. Excellent stuff my man.
Just got caught up on recent videos. The video on checking cylinder and cleaning the bore made me double back on reassembly of my echo cs302! Glad that was covered. Just finished restoring a 1952 Strunk 3-19. That project took 4 months and the saw I found out was built in my home town of Coatesville Pa. Thank you for all your help. Think I have a new sickness!!!
That was some good solid information, easy flow of gasses and ease of use . Great video 👍🇬🇧
It's worth noting that more air equates to more fuel, which is more oil to the bearings. More power is better, until the heat becomes excessive... Typically good tuning makes for better distributed pressures on the crank and bearings. Finding efficiency is a fun game!
Pipe sounds great!
Hey Tinman, thank you for sharing your information that you have learned.
👊✊👊
One of the thing i like the most is that the muffler isn't sitting so close to the crank cases. The amount of heat sinking into the front of the case is huge especially when you are blocking up big logs and there isn't much air flow at the front of the saw. Plus, we all need more crack in our lives(not the drug kind). Cheers Tinman. That Harvey knows a thing or two.
That’s actually a great point. Temperature is the anti-supercharger. Higher temperature = less fuel + less oxygen at the same pressure.
Love watching and listening to saws dancing on the table 🤪
I agree about the tuned pipe... If I'm gonna have that monstrosity on my saw, I want it to make substantial power. A turbo should give the back pressure I need...
Great info Tubman.
Thank you 👊
I just built a muffler mod for my 372xp from one of the chinese aftermarket "high performance" mufflers with the side pipe exhaust. I cut out the factory exhaust pipe which was tiny, it would have been a close fit for a pencil... and opened up the hole and welded in a piece of 3/4 schedule 40 pipe(.680" ID) trying to keep as close to the 60-70% rule as I could with what I had on hand. This muffler has the baffle in it, but (looking from the back of the saw to the front as you're holding it) it has a huge port in the baffle at the bottom right corner to let the exhaust gas flow from the rear chamber of the muffler to the front chamber. I didn't alter any of the baffle. I made my exhaust outlet pipe long enough that it extends inside the muffler to about 3/4" from the left side of the muffler, and exhausts nearly straight out the right side, just in front of the chain brake handle. It has that "POP" in the exhaust, and sitting on the ground at idle, I can see it blowing saw chips around 3-5 feet away or more. It really flows the exhaust out, much better than I ever expected it would with the baffle in there. I don't know if it's making any more power, it kind of seems like it pulls harder now, but at least it isn't burning the crap out of my hand now when I'm buried in a long bucking it up like the OEM top port muffler did. That was the entire motivation for building the new muffler.
What do you think about mufflers with the baffle in them? Would you leave it in there or take the muffler apart and remove the baffle? Is there anything I could do to increase the performance of this muffler? It does seem to be working good, the throttle response is nice and snappy, I'm happy with it so far in the 4-5 tanks of fuel I've ran through it. But if I can get a bit more out of it, I'm up to doing it
I have watched several chainsaw videos where they hollow out the mufflers and make the exit hole larger VS an untouched stock muffler and the modified mufflers always make more power as proven on a dyno
You can add a fairly large spacer where the gasket goes and increase the capacity of air the stock muffler holds which is a easy cheap way of adding a little air coushion kinda like an expansion chamber. I like what you do on your channel man. I've built old school saws for a long time. Mostly old steel body stuff but just ordered a new 550 xp to port and see what the new stuff is capable of lol. From what I'm seeing the new saws rip as is and with some port work should be little monsters.
Lovin it! Great bench talk!
Looking good Tinman 👍.
2 strokes most definitely want an expansion chamber and a funnel to a small outlet. The size outlet determines the higher or lower... Rpm where the power is delivered. The larger expansion chamber gives a cushion of air and increases the usable power. Large expansion chambers are a must in high performance 2 strokes in my opinion. Look into dirt bikes, snowmobile, and mostly into gas powered rc cars and rc planes
Between you, Harvey and Hopper about every question you could think of can be found
I have 2 mac 10-10's and I wonder how a combo of both this style of pipe and the one you made for bucking would look/work. Awsome video and exceptional explanations as always Tinman!
I have a Mac 10-10 also and I was wondering the same thing
With that design, it would be cool if you made the thicker tube longer, then welded a big nut on the end, with a big bolt on it, then you could have an adjustable length from the exhaust port to the flat end of the straight shot, where the sound/exhaust pulses bounce off, to see if you could get the exhaust gasses to keep intake charge in better, like a tuned pipe on a dirt bike. Can't remember what it's called, scavenging? Anyway, great channel, keep it up.
Thanks again. Bruce from Alberta
Just fixed my welding partners sons stihl today, sap had the linkages and spring in handle totally stuck in pine sap, and give it a tune up
Hi my friend. Would love to see a comparison video of that saw cutting with that pipe vs the old muffler u had on it .
I understand Tinman, keep up the good work!! Ken
Great video sir!!❤️
Great video good information
Great show .!!!!! Keep it coming brother. 🦾🌙☀️🔥
Good class you have Good 👍 times sawrus Trees-R-Us Hibud
Just watched this video. Saw Ironhorse put this style pipe on a saw a couple of years ago. I built one for my Stihl 039, it works. Saw is much snappier. Stock and modded saw
So maybe dumb question, but if going through all this trouble to make the muffler that will flow better, why not just go without one?
That's a great question. 2 strokes need to scavenge some of the unburnt fuel and exhaust that is sent out of the exhaust port.
So if you run one without a pipe then tend to lack power and run lean.
@@tinmanssaws I see, makes sense now. Thanks 👌
Good old CANADA 🇨🇦🇨🇦🇨🇦 it went from minus 32 to plus 3 in 24 hours here in ONTARIO crazy weather part of being 🇨🇦🇨🇦 French toast maple syrop and sausages lol don't forget bacon🥞🥞🥞🥞🥞😁😁😁😁✊✊✊ cold weather stay inside breakfast ,warm everyone's heart♥️♥️be safe everyone
Try 2 below maine
Great channel!! Love it!
Hey Tinman thanks again for more interesting viewing, and a thought towards another project for the list…..haha
Hey Tinman which welding do you normally use on the pipes? Can you braze it or is that not strong enough?
I use a 110 arc welder
Braze works for sure, I’ve welded a couple using the tig gun but have had better luck drilling a hole and using a muffler outlet
I...personally mig or tig almost everything that small, but any welding or braizing process will work absolutely same end result if you know what ur doing, if ur good at braizing, whip out the torch, will be more than adequate
Braizing yields around 40sum thousand tensile strength standard welding is standard around 60 to 70 thousand for perspective do its way strong enough, I've made hydraulic fittings...mate how they shouldn't braizing many times and always holds also for dissimilar metals rather tig or torch brazing
Thanks guys, all good info. I have been planning a pipe for my Stihl but I don't have an electric welder so I was going to just braze it ☝.
Great video sharing
Good job brother!!! Airborne55! Here.
Very cool man
Thanks Tinman. I like this style of pipe I'm trying one right now it pulls good. Sounds good. It's on my 372xp
What are we going to build next.
Oil mix 1:33 ?
Great video. I only have a stick welder so thin pipe is a challenge, what’s your thoughts on 1/8 pipe?
if you get thinner electrodes you can weld thin stuff. Id just practice before burn holes in your finished product.
Go to walmart, they sell 1/16 rods, for stick, fast hot flash tacks stacked together will work just fine and look like dimes, dont be afraid of the heat, high hea mean fast travel means less heat input, only thing with 8th is weight otherwise should be no diffrent really
If you ever get down to Virginia please let me know...I would like to meet you!
I did one with dual exit and my goodness what an animal my 372!
Same here on bb ported, harves design I call it the sink faucet yeah it works
Nice
I didn't know you were a road racing fan. I'm from Oklahoma and used to be a race bike technician for HSBK racing with P.J. Jacobson riding Moto America for us.
Tinman how about an anodized aluminum one just like that been on my mind for awhile and I got all the stuff and be a major heat sink...thoughts?
Hey Tinman have you done any pipes for a 572 or plan on doing any?
thank you tinny!
Love this pipe!!
So many variants of building a pipe. Not for tin man necessarily but for the commenters. Hot air goes up cold air goes down. Might help others with building a pipe!
Great job
Nice. Has this style been tried on an Echo 501P?
Hi Tinman my name is Tyler McLaughlin and I run a 272xp for cutting Cedar blocks currently having a small issue with getting my oiler to push enough oil and was wondering what is your favorite muffler say from Amazon ?
The single exit farmertec with enlarging the exit and shoving the pipe down at an angle to the corner and welding it in is a effective very easy and fast muff mode to make, blow that hole out bigger slipped bigger piece in a out 3/4 t 2 inches, burner in, roughly 5 min fix
You can use some thin pipe to save weight.. it does not need to be made from 3mm pipe
Mr. Tinman my main saw is a stock 1984 Husqvarna 181 se would that size pipe be a good size? Or should I look for something slightly bigger in diameter.
I've got a 220 mig welder, I just need the steel to make the pipes!
Autozone, exhaust section, get u hooked yp
What do you think of the bark box? Do they help with cooling and performance?
Love to know all the diameters on the pipe id love to try a couple on a couple saws of mine 066mag an a ms461.
That's a great saw and wicked pipe. How much to build me one Tinman. I'd love to try it out on my 268 stock. Let me know an I'm in. TC great content again. MahaloTinman🤙🤙🤙...Tdawg
Hi im from Fiji island. Wats the difference between 272xp and 281. Can we use 272 piston din 281xp and viceverser
I'm modding the muffler on my cs590 so should I gut the original and make 2 small pipes coming out out the front or put am single pipe coming out the side of the saw? Appreciate your response if you happen to answer. It's a new saw
Hey man..Iam keen to pipe my hasqavarna 272xp.But am not 100% sure is reliable. Please advise.
In future i would make a pipe like this for my 372 :) this pipe is a beast ;)
Not sure how yours turned out so quiet my ironhorse style pipe is ridiculous loud and I love it on my 372xp big bore ported saw
Thank you!!
People don't realize how much power it takes just to pump air through the engine. The parasitic losses from the flywheel fan, pumping air, and the chain are huge.
Would this work with a 455 rancher husky
Had a friend who worked in a racing speed boat shop and they would spend days trimming pipes and sometime a whoops moment would come along and another set had to be built. The word extractor seems to fit the name for these builds. What does everyone think. Cheers everyone
nice pipe ! just finished my 262xp rebuild i see that the exhaust is not really great , the carbon just shoot on the cylinder when theres no screen on it. it will be hearthbreaking to sell this saw ! My first one
You want to sell that echo bar mounted on shelf??
Tinman, have you ever experimented putting a pipe like this on the newer husky’s? Like your 562xp? I haven’t seen much out there other than a mod to the can.
I'd like to pioe my 562 but haven't had the time to build one.
@@tinmanssaws right on. I’ll wait patiently lol. Saying hello from up north in Flin Flon. Take care Tinman ✌️
Do you ever have to worry about wood chips getting in the pipe?…would it hurt to put a screen on end
Double dawg dare you to just put three 3/16 wholes in the lower portion of the stock can.
i remember a honda hrc engineer saying they got over 200hp out of the honda nsr500 after spending months on pipe design. Then suzuki basically was allowed to darn near copy the nsr500 entire engine design.
What size pipe would you put on a 1998 141 husky
How did you kill it with the pull rope?
What's your thoughts on a 562 xp pipe mod
I wonder if using a Tesla valve type of design would work for an exhaust 🤔
Thats the fun of this stuff, you never know what's going to work.
TINMAN what diameter is the chrome exhaust tip please
3/4"👍 @12:20
Edit: the timestamp was correct at least😅
@@skravlesen thx buddy😁😁✊✊✊
It's 3/4" I'd Stevie
I like making them out of aluminum
The pipe is a nice design it's right up there with uncle Harvey's dual scrench pipe , but the best sounding chainsaw I ever heard was the old echo 650 evl , you knew what the saw was when you heard them running in the woods !
1:40 oil mix is ok ?
I would call that a resonant muffler. Definitely not a tuned pipe.
TINMAN LOVES THAT SAW
Single exit pipes are king
John's Custom saws has expansion chamber pipe check it out!
some thing fell out at 19.35
Probably a muffler bearing
Man that saw sounds mean😂 best part about performance mufflers they sound amazing but they also make the saw preform ten times better. I like how there just not all noise it actually serves a purpose😎
can u please help me locate cylinder and piston for my jonsered cs2165 turbo pleaseeeeeeeeeeeeeeeeeeee
Pipe must not extend beyond dogs... got it.
A tuned pipe sucks!
Lol
Would the size of a stock muffler act like a chamber? Many you could make a pipe that works on 1/2-1/4 waves that would be smaller?
A “practical pipe” or a tuned pipe, one you can use and one looks cool and might have a little advantage. I’ll choose the practical pipe more often.
The second problem with the stock muffler is the port size is larger then the exit. It will create back pressure preventing the air pump from getting the bad air out.
Sound a lot quieter muffler to me and I hope it heats up where you at I live in the mountains in Northern California and we had over 4 ft of snow it’s slowly warming up hear bottom line I feel for you
I like my saws nice and warm, like holding a Ferrari in your hands.
I built myself a 350 and it runs different than the others I have done. It doesn't have that pop/cackle at idle. I used a lot of epoxy in the engine to improve flow, so maybe that's why, I dunno. I think I'm going to try making one of those pipes and see what happens. It's just over 5hp right now.
I'm sure Buckin already showed you tinman
evening tinman!!🙋
Evenin joneszzy
Give me the word Tinman and I’ll make you a nice stainless exhaust.
“4 1/2” to fit all this pipe in there” all I need most days. 😜
Tinman I sent you my pipe mod to your Instagram don't think you seen it
Just put more wood on the fire! Keep it hot lol.
I run a pipe off of my cr 500 dirtbike on my saw
Great show .!!!!! Keep it coming brother. 🦾🌙☀️🔥
can u please help me locate cylinder and piston for my jonsered cs2165 turbo pleaseeeeeeeeeeeeeeeeeeee