Echo cs 590,600,620 porting/mod/build thread

[Red97]

Ok, these saws have me intrigued.

Have a couple 590's in the mail as we speak.

So for those that have them, and or run them what ya think?

This is what I have so far

Transfers

Very small squish band and a tapered chamber.


Rather large intake.


Small exhaust.


Slightly domed piston with a taper cut in the squish area.

Just from the exhaust size I imagine these are rather torquey saws in stock form. Looks like I have about.05 before freeport, won't know timing numbers, or squish till I get the saw.

Just looking at the jug, seems a bit is still left on the table.

Discuss.

 

[awol]

It's not hard to get more out of these saws, but it is hard to make them run like a ported 562. The killer is the small carb, boot, and intake spigot. I have not tried any other carbs on one. When figuring port timing, remember the bore to stroke ratio is more even than most modern saws, 45mm bore by 37mm stroke.

 

[Red97]

It's not hard to get more out of these saws, but it is hard to make them run like a ported 562. The killer is the small carb, boot, and intake spigot. I have not tried any other carbs on one. When figuring port timing, remember the bore to stroke ratio is more even than most modern saws, 45mm bore by 37mm stroke.

Thank you for the reply.

Seems these saw would get a rather healthy bump in compression with minimal off the base.

Didn't realize the stroke was that long... that piston is really moving. That explains some things I've seen in my older jug.

I plan on getting the unlimited 620 coil, may not help much, but it does have a different ignition curve than the 590,600 coil.

 

[bikemike]

Long stroke means more torque

 

[Poleman]

You'll like the 620 coil!! I've ported two of these and in my opinion that is what was lacking.....with that said you also may run out of carb but have never switched one over to know.

The 620 is the ultimate package with bigger carb and unlimited coil. I've ported one of those and the guys using it in production and running with the big dogs with it. He's since sold his 576 and ported 372 and this is his main saw running a 28 inch bar.

 

[Red97]

You'll like the 620 coil!! I've ported two of these and in my opinion that is what was lacking.....with that said you also may run out of carb but have never switched one over to know.

The 620 is the ultimate package with bigger carb and unlimited coil. I've ported one of those and the guys using it in production and running with the big dogs with it. He's since sold his 576 and ported 372 and this is his main saw running a 28 inch bar.

Thank you, that is quite a testiment to the 620...

Just trying to get a porting/ info thread started on these saws, seems quite a few on as so hoping to get one started here.

In the ones you ported, did you feel the carb was really holding it back?

Don't even know what the stock coil is limited to, but wonder if filing the key with the stock coil would help?

 

[rburg]

The only 590 I have run was ported by Awol and it was a nice running saw.

 

[Mastermind]

The 600Ps that I've ported have been amazing. Every time I do one, I think about what a bad ass saw it is.

 

[bikemike]

620 and the 620 pw are the same saw with a different handles. Is that 1 a unlimited coil bigger carb saw then or is the coil a aftermarket part

 

[bikemike]

I was thinking of getting a new 800p but very few vids of them in action and seems to not have a good working range for rpm

 

[Red97]

620 and the 620 pw are the same saw with a different handles. Is that 1 a unlimited coil bigger carb saw then or is the coil a aftermarket part

From what I have gathered, the 620 has the biggest carb of the 3 and unlimited coil.

 

[Simondo]

The 620 is getting a serious rep from all i see and hear..even out of the box folks say there a grunty saw.
In fact , Echo saws over all seem to be well liked and good on the reliability front .

 

[Making Sawdust]

I can't speak of how a ported 620 is, but my stock one is a great saw, it was pretty unimpressive until it was broken in however. It's really been a dead reliable and capable firewood saw for me. Just my experience with it though

 

[Red97]

Well 1 saw arrived today. Sure enough scored. Dosent look horrible tho. Going to check port timing before I tear it down.

While I had the muffler off did a lil muffler mod




Still have to go through and gut it. But not bad for a 5 min muffler mod.

 

[Poleman]

I don't really think the carb was holding it back as much as the limited coil was....just seemed like there was so much more in there wanting to come out. Now if you upgraded the coil there could possible be a carb issue.....but I dought that would happen. If I recall the 590 always seemed to run a little rich but when it would clean up stand back cuz it just shifted gears!!!! The ported 620 just flat ran top to bottom!!!! Very impressive saw!!

 

[Red97]

I don't really think the carb was holding it back as much as the limited coil was....just seemed like there was so much more in there wanting to come out. Now if you upgraded the coil there could possible be a carb issue.....but I dought that would happen. If I recall the 590 always seemed to run a little rich but when it would clean up stand back cuz it just shifted gears!!!! The ported 620 just flat ran top to bottom!!!! Very impressive saw!!

Nice, going to time this saw, and check squish in the am. Then try to figure out where I want to go.

Do you happen to remember where the comp ended up on the ones you ported?

Plan on running a 20 or 24" bar on it.

 

[Poleman]

I'm thinking stock they were 150-155 and after gasket deleat was 175-180.....can't remember if I cut anything...sorry.

 

[Red97]

I'm thinking stock they were 150-155 and after gasket deleat was 175-180.....can't remember if I cut anything...sorry.

No worries, mine is currently sitting at 70psi

Hoping to get it up round 200psi when all said and done.

Thank you for the help.

 

[drf256]

Thanks for starting this thread Red.

Nice muffler deflector

My understanding is that the 620P has a totally different jug and timing than the 590/600.

Where is the ring pin?

Those uppers are pretty beautiful. I can't see any gains there myself.

 

[jake wells]

i had a 590 a few months ago and it was down right nasty did a base gasket delete went whole hog on the muffler pulled the limiters and replaced the limited coil in it from a 620pw.
added a 620 wrap handle to. pulled a 24'' like nobody's business had great torque and the power band was smooth plus it was reliable but my old man needed it so i sent it his way.