Echo CS-8000 Mod

[FreakinCoolUsername]

I am looking to mod a CS-8000 as for a 80 cc saw it seems like its lacking. I am considering a Gasket delete, cylinder port, and muffler mod but their is a problem... i don't know how to do any of that. I Have rebuilt many saws but never really modded them. Any info on how to go about this would be greatly appreciated.

 

[mountainlake]

You sure can open up the muffler, most Echo saws come clogged up.. Steve

 

[link]

I am looking to mod a CS-8000 as for a 80 cc saw it seems like its lacking. I am considering a Gasket delete, cylinder port, and muffler mod but their is a problem... i don't know how to do any of that. I Have rebuilt many saws but never really modded them. Any info on how to go about this would be greatly appreciated.

OK, just consider less is more.
I learned a lot from this post - that refers to a series of other threads and posts from other forum members:
https://www.arboristsite.com/threads/365-372-kit-builders-thread.357338/post-7703794
Remember that any material you remove from the low end (crancase, ports) will decrease the vacuum and compression in this part of the engeine - so make it count. Less vacuum in the low end will suck in less fuel/air through the carb, less compression in the low end will give less fuel/air to the cylinder.
Also, enlargening (widening) the port windows in to the top end without enlargening the rest of the ports will decrease the gas velocity in to the cylinder - which is not what you want. The port windows in to the cylinder is a "nozzle", I'd suggest not doing too much with them.
Widening the exhaust port and make sure all port transitions is dynamic might be the most obvious improvement - more power but less fuel efficiency.
As for the gasket delete, you improve compression and tourque, but the ports will be less opened and you change the timing a little too - all of this points to less rpm and therefore HP, but to more torque and power at the mid range rpm.
As for the muffler mod you should consider the area of an 1" round hole is about perfect for a 70-80cc, so that may be more than "one" hole. Else the muffler should be empty with as much open area inside as possible.

Be on the safe side, less is more..

 

[FreakinCoolUsername]

OK, just consider less is more.
I learned a lot from this post - that refers to a series of other threads and posts from other forum members:
https://www.arboristsite.com/threads/365-372-kit-builders-thread.357338/post-7703794
Remember that any material you remove from the low end (crancase, ports) will decrease the vacuum and compression in this part of the engeine - so make it count. Less vacuum in the low end will suck in less fuel/air through the carb, less compression in the low end will give less fuel/air to the cylinder.
Also, enlargening (widening) the port windows in to the top end without enlargening the rest of the ports will decrease the gas velocity in to the cylinder - which is not what you want. The port windows in to the cylinder is a "nozzle", I'd suggest not doing too much with them.
Widening the exhaust port and make sure all port transitions is dynamic might be the most obvious improvement - more power but less fuel efficiency.
As for the gasket delete, you improve compression and tourque, but the ports will be less opened and you change the timing a little too - all of this points to less rpm and therefore HP, but to more torque and power at the mid range rpm.
As for the muffler mod you should consider the area of an 1" round hole is about perfect for a 70-80cc, so that may be more than "one" hole. Else the muffler should be empty with as much open area inside as possible.

Be on the safe side, less is more..
View attachment 986643

Thank you for all the info, i do have some questions. What do you mean when talking about "make sure all port transitions is dynamic". I was also under the impression that the muffler could not be empty, due to it affecting the timing?

By "Also, enlargening (widening) the port windows in to the top end without enlargening the rest of the ports will decrease the gas velocity in to the cylinder - which is not what you want. The port windows in to the cylinder is a "nozzle", I'd suggest not doing too much with them." are you saying i should many focus on enlarging the exhaust port rather than the intake and exhaust?

"As for the gasket delete, you improve compression and tourque, but the ports will be less opened and you change the timing a little too - all of this points to less rpm and therefore HP, but to more torque and power at the mid range rpm." -Is there any way to match the timing after removing the gasket. I am not so much looking for fast cutting (hp) but just power thats gonna go threw anything. On the subject of lower rpms, wouldn't that combat the inefficiency of the other mods?

 

[FreakinCoolUsername]

You sure can open up the muffler, most Echo saws come clogged up.. Steve

So true, these things are a little to quite in my opinion.

 

[rmotoman]

I am looking to mod a CS-8000 as for a 80 cc saw it seems like its lacking. I am considering a Gasket delete, cylinder port, and muffler mod but their is a problem... i don't know how to do any of that. I Have rebuilt many saws but never really modded them. Any info on how to go about this would be greatly appreciated.

Sharp chain and run the front guides on the chain lower than normal. The power band is in the mid range. People try to rev these saws and are disappointed. They have plenty of power if ran in the power band.

 

[link]

Thank you for all the info, i do have some questions. What do you mean when talking about "make sure all port transitions is dynamic". I was also under the impression that the muffler could not be empty, due to it affecting the timing?

By "Also, enlargening (widening) the port windows in to the top end without enlargening the rest of the ports will decrease the gas velocity in to the cylinder - which is not what you want. The port windows in to the cylinder is a "nozzle", I'd suggest not doing too much with them." are you saying i should many focus on enlarging the exhaust port rather than the intake and exhaust?

"As for the gasket delete, you improve compression and tourque, but the ports will be less opened and you change the timing a little too - all of this points to less rpm and therefore HP, but to more torque and power at the mid range rpm." -Is there any way to match the timing after removing the gasket. I am not so much looking for fast cutting (hp) but just power thats gonna go threw anything. On the subject of lower rpms, wouldn't that combat the inefficiency of the other mods?

You have a powerful saw to begin with - remember that.

Dynamic:

 

[link]

Make sure the muffler is an emty shell without any internals. Empty, as a large volume inside as possible - no catalyzator that takes up any space inside there.

 

[link]

are you saying i should many focus on enlarging the exhaust port rather than the intake and exhaust?

 

[link]

Yep. Dont change the timing (opening time), but you can make the exhaust port wider. Read the thread reference I referred to...
And then you will know how much you can widen it and how the port should be shaped and bevelled or edges rounded accordingly.
And you could look at my template - it states a formula of how wide you can make the exhaust port - theoretically, based on your cylinder.

 

[link]

You will know it all by heart - if you read the reference made by much more experienced guys than me. Its at your finger tips, just follow the link...

 

[FreakinCoolUsername]

You will know it all by heart - if you read the reference made by much more experienced guys than me. Its at your finger tips, just follow the link...

Thanks again im really excited to try and learn this side of the hobby.

 

[FreakinCoolUsername]

Sharp chain and run the front guides on the chain lower than normal. The power band is in the mid range. People try to rev these saws and are disappointed. They have plenty of power if ran in the power band.

I do agree these are already very powerful saws and i like that they don't rev like a stihl, its why over the past couple years i have moved more tawords echo products. But the 80 cc saw line from echo is behind when you compare what length bar it can run. Mine has a brand new cylinder and a new piston, but struggles stay consistent in a cut with a 28" bar and skiptooth chain. Of course the only saws i can compare it to are a pro mac 805 and homelite 550.

 

[link]

I find that disturbing, 80cc should be able to run a 28. My little 360 modified saw is very agressive.
Thats 35cc with a 14" bar, this is a stock 360 with an opened muffler:

 

[LuDookie]

Consider tuning. My 680 will run a 28” with authority. Not a fast, revy saw but strong for 66.8cc.

 

[FreakinCoolUsername]

I find that disturbing, 80cc should be able to run a 28. My little 360 modified saw is very agressive.
Thats 35cc with a 14" bar, this is a stock 360 with an opened muffler:

Well i have always wondered if something wasn't right with it but it runs great just struggles in large cuts. When i rebuilt it it got a new carb, cylinder, caber rings, and the 800p piston. By all means it should have plenty of power, any thoughts on what it may be?

 

[LuDookie]

Can’t be sure. I know the 680 was the doggiest saw ever when new. Took several tanks for it to open up. Manual says 12,500 for RPM’s but I’ve run it pig rich at just above 10 and it’ll pull but I’ve found just around 12,000 at sea level is a sweet spot. It makes its power on the low end.

 

[link]

Well i have always wondered if something wasn't right with it but it runs great just struggles in large cuts. When i rebuilt it it got a new carb, cylinder, caber rings, and the 800p piston. By all means it should have plenty of power, any thoughts on what it may be?

Perhaps you just expect too much from it, 28in buried in wood is gonna be tough for any saw less than 90cc.
I consider a 20 to 24in bar on a 70 to 80cc, it won't make you disappointed a lot at least. It should be able to pull 28 buried, with some patience and a sharp chain.
But when people brag about having a 28 or a 32in on their Husky 372, Dolmar 7910 or ms460, they likely do not usually use the full lenght of it.
If they did, they would probably not brag about it... no problem to stall a 70cc in 20 inches of wood if you are just a little impatient.

 

[rwoods]

I do agree these are already very powerful saws and i like that they don't rev like a stihl, its why over the past couple years i have moved more tawords echo products. But the 80 cc saw line from echo is behind when you compare what length bar it can run. Mine has a brand new cylinder and a new piston, but struggles stay consistent in a cut with a 28" bar and skiptooth chain. Of course the only saws i can compare it to are a pro mac 805 and homelite 550.

Try this thread - https://www.arboristsite.com/threads/echo-cs-800p.290187

I don't know about Homelite, but all of my stock 82cc MACs will spank my stock 80cc Echo. Echo is one well-built saw.

Ron

 

[Sierra_rider]

I am looking to mod a CS-8000 as for a 80 cc saw it seems like its lacking. I am considering a Gasket delete, cylinder port, and muffler mod but their is a problem... i don't know how to do any of that. I Have rebuilt many saws but never really modded them. Any info on how to go about this would be greatly appreciated.

Get some solder and measure the squish. On a saw, I'll go in through the spark plug hole until I hit the cylinder wall and then rock the piston over TDC a few times.

If the stock squish is around .030", you got a good candidate for a gasket delete. The gasket is probably around .020" thick, putting a layer of motoseal on will probably add back about .010", for a net loss of .010" squish clearance. Obviously, remeasure squish after you're done, just to make sure it isn't too tight. I shoot for about .020" squish when I'm milling cylinders.

Muffler mods are pretty easy. People argue about it, but I'm of the opinion that chainsaw mufflers are there purely for noise control, i.e. they don't provide tuning characteristics like the expansion chamber on a dirt bike. IMO, more open is better...at a certain point, you aren't gaining anything by going more open. As already said, gut the inside of the muffler(IDK if the Echo even has any baffling inside.)
The best bet is to weld on deflectors to whatever new openings you make in the exhaust. Some people cut slits in the exhaust and then pry them open to make louvers. On saws with one piece mufflers, I'll drill a hole and then weld a tube inside that hole. On my Stihls with 2 piece mufflers, I make a new muffler cover a la Bark Box style.

Porting is a little more complicated. As others have said, don't change port timing unless you understand how it's going to affect the power. On the face of it, I'd consider raising the exhaust port on a saw that didn't have much top end power, but that's an overly simplistic approach. Other factors like blowdown and intake duration. I kind of have a formula I stick to for timing numbers, but I'm not a pro tuner by any means.

I generally widen all the ports, just trying to get as much flow as possible. Like I said, I'm no pro, I just kinda imagine what shapes/sizes would give the most flow and velocity. I've built some bad-azz saws, I've also built some duds. Your Echo is probably a good saw to experiment on...Echo parts usually seem pretty affordable compared to the big 2, so if you do wreck a cylinder, it's not the end of the world.