Closed Port for Husky 50, 51 or 55?

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The Closed Port P/C's came on some of the Husqvarna 55 EPA saws. They will have a compression release and easily identified by the +++++++++ across the bottom of the jug.

I have two of them here, they have great power for the cc's and my "go-to" saws for limbing and most of the tops I'm cutting these days. The power curve is narrow and strong not wide/broad/flat like the 55 Rancher open port 55's. I'm really fond of all the Husqvarna 55 platforms and wouldn't stick my nose up at a 55 Rancher open port in good shape. Even with that said if you had a closed port and open port 55 laying there and headed to the woods to cut some firewood unlikely you'd NEVER find yourself reaching for the open port version......IMHO.......

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The Closed Port P/C's came on some of the Husqvarna 55 EPA saws. They will have a compression release and easily identified by the +++++++++ across the bottom of the jug.

I have two of them here, they have great power for the cc's and my "go-to" saws for limbing and most of the tops I'm cutting these days. The power curve is narrow and strong not wide/broad/flat like the 55 Rancher open port 55's. I'm really fond of all the Husqvarna 55 platforms and wouldn't stick my nose up at a 55 Rancher open port in good shape. Even with that said if you had a closed port and open port 55 laying there and headed to the woods to cut some firewood unlikely you'd find yourself reaching for the open port version......IMHO.......

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"you'd find yourself reaching for the open port version......IMHO......."

Really.
I would have thought the closed port would win.
I have two complete Husky 50's. My plan was to build/port one in open port and the other as a closed port.
I have a open port 44 to 46mm kit coming. One jug and piston are good.
So maybe I'll do one as 44 mm open port and the other as 46 mm closed port.
 
Oops, made an "adjustment" to the original post.

Husqvarna closed port P/C's are pretty much all like that based on the ones I've owned over the years.

I've had at least a dozen 51's and 55's, plus a MINT condition 50 special which has been in storage since a few weeks after it was new. All of the open port P/C versions have wide/broad/flat/smooth power curves compared to the CP's. The CP's need a compression release and "raspy" exhaust note when idling. They love high RPM's in and out of the cut.

My 268XPS is the same, raspy, about yanks your arm out of the socket when starting it, and LOVES high RPM's in and out of the cut. Erring just a fuzz-nut rich with the tune it's well over 13,000 rpms no-load and four-stroking nicely.......
 
Correct, my 262XP wasn't nearly as '"raspy", and broader power curve. The 262XP is a great saw, even better if it took the large mount bars. Believe it or not I like my CS-600P/620PW better. Mostly because they have equal to if not a touch more power, plus they refuse to clog up cross cutting, which I find myself doing a lot of these days......
 
But is a closed port faster cutting in an 18 in bar full of hardwood? I have a good running open port 55 and was wondering myself if it was worth the expense to go to a 55 closed port piston/cylinder.
My 365 Special is open port and can't tell any difference between its closed port equivalents. I'd say don't sweat it and use her as is.
 
The 50's have two diameters where the jug meets the case. I kept my 50/55/5000 out of several 50cc saws including two 346xp. Mine has a 5000 jug with a golf piston, 50 crankcase with 55 carb and top cover. I don’t remember what the piston was for, but I had to grind the boss to fit the rod.
 
Did you swap the jug? Specials should be closed. Supposedly the last of the 365's had the closed port jug as well before the special designation.
Just curious and gathering info for reference.
I think as it's an Australian version they are different. I believe the closed port cylinders were an EPA thing and there are less strict requirements over here compared to NA. That's what I can gather anyway but information is limited.
Mine is a 2001 build.

I had a feeling at least some of the Canadian released specials were also open port but who knows!
 
The 50's have two diameters where the jug meets the case. I kept my 50/55/5000 out of several 50cc saws including two 346xp. Mine has a 5000 jug with a golf piston, 50 crankcase with 55 carb and top cover. I don’t remember what the piston was for, but I had to grind the boss to fit the rod.
What brand saw was the 5000 jug from?
 
If I find a closed pot to fit the 50, I will find out.
I don't think so. You have to let it rev and with a full 18 inch bar you have to let it ride. It shines cutting the smaller stuff. It's faster than a stock 455 with the full 18 inch buried. I just ran both recently on the same wood. I sold my open port 50s, but I think they had more grunt, you could put some pressure in the cut.
 
I quite like the 50's, 50,51,55. I built my father a 51 with a AM 55 c/p and it's still going strong years after I built it (he rides em hard and puts em away wet). I had a selection of my saws last time I was at his place and he would consistently pick up his 51, failing that he would pick up my 026 Stihl.
 
Correct, my 262XP wasn't nearly as '"raspy", and broader power curve. The 262XP is a great saw, even better if it took the large mount bars. Believe it or not I like my CS-600P/620PW better. Mostly because they have equal to if not a touch more power, plus they refuse to clog up cross cutting, which I find myself doing a lot of these days......
I don't believe it, lol.

anyway, as I recall, your 262xp was a later detuned model. Mine is the early model and has more power everywhere (especially on top) than my 590 echo which is not what you have compared to I realize.

aside from that, the echo simply is nowhere near the husky in terms of handling.

but yet I still like my 590, as it is definitely a good saw, but was also definitely an aquired taste for me. I was pretty underwhelmed when I first got it, but have learned to appreciate its strong "midrange" type of power. I wish it had some more revs for a screaming topend is all. And I wish the darn choke knob didn't prevent me from getting into a comfortable between the legs starting position. That knob could be almost 1/2" shorter. SHOULD BE 1/2" shorter. That is really my only genuine complaint with the echo 590.
 
Don't know about "de-tuned" but my 262XP was a great running saw. Some will say if you had the Husqvarna top end with the compression release they weren't as fast as the other variety. Didn't want to make me go out and bury it in the back yard, but I didn't use it much once I picked up the Echo 600P. My 600P is an early model and doesn't share the same top end and limited coil as the CS-590's. Since I own all three, the CS-590, CS-600P and CS-620PW (X series) I can tell anyone reading this that there really isn't a lot of power difference between all of them. I've ran them (test cuts in the same log) with the same bar and chain back to back and the differences between all of them are very minor and hardly noticed. The problem with my testing is that I should have moved up to a 24" or even 27" bar and a much bigger log. I made cut after cut after cut the day of the testing and really only a slight difference between each one.

Many open port 55 Ranchers came with 20" bars and 3/8" chain set-ups. They are far better suited to .325" and 18" bars....IMHO. They don't have the power to effectively pull 3/8" and certainly not a 20" bar. Still excellent saws and plenty of them still around getting it done. I've tried to find 55 EPA saws with the CP P/C's a few times and most are seized or have some material smeared over the rings and down on compression. I got really lucky with my first CP 55 and was able to clean it up. The second had an oil leak and loose muffler but perfect P/C. I bought several others and they were JUNK so quit chasing them on Ebay and settled for two good ones. At the same time I had two 51's, and two really nice 55 Ranchers in the inventory and one by one sold them off.

I never once did any timed cutting between the 55 CP and open port saws but it doesn't take a rocket scientist and test lab to know the CP version is stronger in the cut. They just have a peaky power curve and love high RPM's. The open port versions have a wider RPM range and smoother power curve but not as fast as the CP's. I also have one of the cleanest 50 Specials in existence. My brother-in-law purchased it new to cut down three small trees in his back yard then put it away. Sadly he passed away and I inherited the saw a few years ago. His wife had carried it to a dealer and they told her it sat too long with fuel in it and was "junk". To my surprise there was nothing wrong with it and it roared to life after a dozen or so pulls and ran flawlessly. I put it back in storage and haven't looked at it in years. Maybe if I ever wear out one of these 55's I'll start using it, but it doesn't appear that's likely to happen anytime soon.........
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