Aftermarket MS660 Performance

[brshephard]

Whats up guys.
I'm looking to get some extra power out of my aftermarket MS660, and I wanted to see what you guys think.
Here's where I'm at so far:

The saw has an aftermarket topend, I set the timing at 100/120/80.
It has the Hyway popup, running about 225psi.
Ignition at 28 degrees BTDC.

What do you think about those numbers?
In the video the saw is turning about 10.5K. 32" bar in 24" Douglas fir.
Seems slow compared to other folks, I haven't widened ports at all though.
Any advice?
I'm mainly using this saw to noodle and mill.

The chain is Oregon full skip square done on my Simington with a blue wheel. Seems to work good.

My first post by the way. Been reading here for awhile though. Started out muffler modding an 026, ten saws later I'm starting to think I have that CAD thing.

 

[trooney]

Welcome! That CAD thing can be fun. Ran ALOT of saws because of it. I'm sure someone can chime in on your setup. Have fun!!

 

[smokey7]

Numbers sound good. Havnt seen too many 660 aftermarket top ends with the intake higher then 84. So you must gave got a good one. How does the saw do when the dawgs are used. To me it ran a tick above a stock oem 660 so thats a good thing which top end are you running?

 

[T.Roller]

I'd definitely widen the exhaust port and intake. I took mine within a thousandth of the edge of the skirts.just watch your ring ends

 

[brshephard]

Welcome! That CAD thing can be fun. Ran ALOT of saws because of it. I'm sure someone can chime in on your setup. Have fun!!

Thanks, cool site you guys have.

Numbers sound good. Havnt seen too many 660 aftermarket top ends with the intake higher then 84. So you must gave got a good one. How does the saw do when the dawgs are used. To me it ran a tick above a stock oem 660 so thats a good thing which top end are you running?

Its an Everest topend. I had to epoxy the intake to raise it up. The original numbers were 97/125ish/84.
I'll definitely dog it next time.

I'd definitely widen the exhaust port and intake. I took mine within a thousandth of the edge of the skirts.just watch your ring ends

Cool, I'll go for some width and see how it goes.

 

[Czed]

Whats up guys.
I'm looking to get some extra power out of my aftermarket MS660, and I wanted to see what you guys think.
Here's where I'm at so far:

The saw has an aftermarket topend, I set the timing at 100/120/80.
It has the Hyway popup, running about 225psi.
Ignition at 28 degrees BTDC.

What do you think about those numbers?
In the video the saw is turning about 10.5K. 32" bar in 24" Douglas fir.
Seems slow compared to other folks, I haven't widened ports at all though.
Any advice?
I'm mainly using this saw to noodle and mill.

The chain is Oregon full skip square done on my Simington with a blue wheel. Seems to work good.

My first post by the way. Been reading here for awhile though. Started out muffler modding an 026, ten saws later I'm starting to think I have that CAD thing.

Welcome to the site
These guy's mess with stihls more than
Me lol

 

[Fruecrue]

Welcome to OPE.
Those numbers sound great, if you can get some more port width, go for it.
Are you running the AM carb?

 

[Chainsaw Jim]

Welcome!

It looks like a damn good runner. You might want to take a swipe or two off the rakers.

 

[Lightning Performance]

What is done to the muffler?
Go go for more exhaust area.

 

[MustangMike]

The Cross jugs come with wide ports, and seem to run well with just a base gasket delete. I have them on an OEM 066 and AM 660s. You can see my 066 at HL Supply - YouTube - Cross vs OEM.

You did not say what mods you did to the muffler, or if you advanced your timing. I do both. May want to try that first to see what your jug will do, as is.

 

[T.Roller]

The Cross jugs come with wide ports, and seem to run well with just a base gasket delete. I have them on an OEM 066 and AM 660s. You can see my 066 at HL Supply - YouTube - Cross vs OEM.

You did not say what mods you did to the muffler, or if you advanced your timing. I do both. May want to try that first to see what your jug will do, as is.

There's still alot you can widen on the ports of the cross

 

[brshephard]

Here's where I'm at now. I knocked about 8 seconds off a 40 second cut and gained about 1k rpm in the
wood.

Here are some pictures:
Intake


Exhaust



Squish Band


Muffler

 

[brshephard]

Here are some more pictures.

Hyway Popup. The popup is about 15 thou.


The bottom ring is pinned inside the piston skirt and the ring comes down into the intake port quite a ways. I opted to take out the bottom ring and go as wide as the skirt would let me. Not sure if that was the best way to go, I figure I had plenty of compression already.

Here is a picture of the ring land way down in the intake:

 

[Time's Standing Stihl]

Looks good.

Let's see some pics of the chain. Looks like you could drop the rakers a tad

 

[brshephard]

Welcome to OPE.
Those numbers sound great, if you can get some more port width, go for it.
Are you running the AM carb?

I'm running the AM that came with the kit.

Welcome!

It looks like a damn good runner. You might want to take a swipe or two off the rakers.

Good idea. I'm at .025 now, I think I'll spin a loop at .030 and see if that helps.

The Cross jugs come with wide ports, and seem to run well with just a base gasket delete. I have them on an OEM 066 and AM 660s. You can see my 066 at HL Supply - YouTube - Cross vs OEM.

You did not say what mods you did to the muffler, or if you advanced your timing. I do both. May want to try that first to see what your jug will do, as is.

I've seen that video. As soon as those cross cylinders go on sale I'll buy a few.
I advanced my ignition from 22 to 28. Seemed to help.
What do you think about my muffler mod? Should I go bigger?

 

[Stihlmar]

What is the everybody’s consensus on widening the lowers? Looks like that’s what you did?

I have been under the impression lately that velocity is pretty important in how a saw can run. Would this widening possibly decrease said velocity?

 

[Chainsaw Jim]

Sharpen the chain. That thing is smoking like hell and burning the wood.

 

[Stihlmar]

And take the rackers to .035 - .04.

 

[Adirondackstihl]

Sharpen the chain. That thing is smoking like hell and burning the wood.

I saw that too.
Sumpin ain’t right wif da chain

 

[brshephard]

I think the smoke is moisture.
Anyways here is some chain porn. I touched them up on the grinder so you guys can see it better.
My top plate is about 22 and my side plate is about 2-4.
Let me know what you guys think. I'll go to .030 on the rakers and try again.