MS660 Exhaust Mod

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

ppipowerclass

New Member
Joined
May 12, 2013
Messages
1
Reaction score
0
Location
Northern Ohio
I have read several different forums on here, and I can't seem to get a completely clear answer. I recently ( 3 days ago ) bought a brand new MS660. I have owned, and still do own SEVERAL stihl saws that i have bought from people, been handed down from family.. etc, etc.

Well, this is technically MY first saw that i can say is 100% mine.... that being said.. I want to tune it up some. From what I have read, it seems the exhaust is key on getting more power out of them, specifically a dual ported exhaust. I looked on ebay, and there were several " aftermarket dual port mufflers ". Is it that simple? a 40 dollar aftermarket muffler and a carb adjustment? or is there more to it? I have also read that the dealership has an OEM dual port muffler.

Now, I am not one for warranties ( especially, since i have quite a few stihl saws that HAVE been used for heavy logging from the late 70's - early 80s that still run very strong ), but in my little older age now, I don't want to void the warranty on a 1000 dollar + saw.

Any feedback would be very helpful... even if it is in the form of a kick in the ass because im posting on the wrong forum, or because this has been asked 1000 times before and I just haven't managed to find it yet.

thanks!!
 
I don't know much about been debating on muffler modding my 044 ...but I can tell you that brad snelling and many other great saw builders mod mufflers..and I reckon it helps performance so id go with the oem dual port cover..good luck
 
You can always buy the complete aftermarket muffler, gut the whole cage inside for better results and retune.
If you have to take the saw back to the dealer, then put back on the stock muffler and retune .
Cheers Wayne
 
Curious to know what you're planning to use the saw for where you're going to be needing more than the stock 7 hp. Why not run the saw as-is for awhile to see whether it's going to hold together, ensure the warranty coverage, and evaluate whether stock power will meet your needs before thinking about any changes? As you know, anything can happen with high performance 2-cycle motors and repairing a blown 660 can be major $$$.
 
Last edited:
My 660 is stock plenty of power for me:blob2: I agree run it stock for a bit then if you want muffler mod it. I say dual port from factory
 
The new 660s need a muffler mod to breathe. They have an opening about the size of a lot of 50cc saws from other manufacturers. I would open the original opening a good bit and if that's not enough put the dual port on or put another deflector on the other side.
 
They are choked up from the factory ( US ) models.
You can always buy the aftermarket muffler as they would be cheaper than stihl's prices and get the daler to fit.
Thay wont pick it as an aftermarket muffler, say you purchased it from a friend and then that way you are covered by warranty.
They do go a lot better with just the dualport muffler on and the saw will look stock standard which is how i like mine to look.
Hope this helps some
Wayne
 
exhaust mod

Buy the Factory dual port muffler cover (Germany vs. China, I pick Germany), and drill out the side port on the existing to make it larger. Take the baffles out as well if they are in. I found an older 046 muffler in great shape in my local shop, it already had the larger opening on the side and no baffles to begin with. Added the factory dual port cover and had it retuned. Worked great for my 460. Certainly you'll see a difference in power but mostly throttle response/acceleration.
 
Yeah, sorry for stating about gutting the cage inside as the 460's dont have them.
I was thinking of the 660 and i replied to a post as well also so sorry for any misleading information in that respect.
Moding your muffler is fine as long as the saw is not under warranty, otherwise just go for a dual port.
I purchased an aftermarket muffler for my 660 and you wont tell the difference in build quality. Wether the steel is the same quality will be seen but they are not that expensive and i can always mod the origional choked up muffler if the other one rusts out.
Cheers Wayne
 
I too just bought a new 660 about three days ago. Awesome saw. I was also looking at the Dual Port Muffler. If i do that, will i have to retune the carb??
 
I bought a new 660 in 2009 and I had the dealer install the factory dual port for me. That would be my recommendation to open up the very restricted exhaust ASAP, it not only increases the performance of the saw it will help with the durability by reducing heat as well

Steve
 
I too just bought a new 660 about three days ago. Awesome saw. I was also looking at the Dual Port Muffler. If i do that, will i have to retune the carb??

Yes. Learning how to tune your own equipment should come before any modifications from factory config. Always.
 
Modding saws is just a fad that will soon pass......

[video=youtube;hyU-bCjnLQo]http://www.youtube.com/watch?v=hyU-bCjnLQo[/video]

:hmm3grin2orange:
 
Send it to your nearest saw porter and never look back. I have both a ported MS460 and MS660 and they are my go to saws. Everyhting else seems well not like much fun to run.

If this is your first true you own it saw then send it out to have it reworked. It took me a while to do it and I have no regrets at all.

My 660 runs as strong it seems as my stock MS880 Scott (Tree Monkey)where you been? We need to talk about the 880:hmm3grin2orange:
 
Curious to know what you're planning to use the saw for where you're going to be needing more than the stock 7 hp. Why not run the saw as-is for awhile to see whether it's going to hold together, ensure the warranty coverage, and evaluate whether stock power will meet your needs before thinking about any changes? As you know, anything can happen with high performance 2-cycle motors and repairing a blown 660 can be major $$$.

Come on Wheelock, what fun is that? None of my saws needed a MM or porting but it sure is nice to have the extra grunt and the awesome sound. I say add a dual port and make sure it gets tuned properly. Add the hd2 filter if you don't already have it. A dual port shouldn't void warranty if its tuned properly.
My 660 and 460 turn heads just like my Sierra with flowmaster 40 series. It's a disease:rock: Maybe a little cad but it doesn't stop at chainsaws for me.
 
Come on Wheelock, what fun is that? None of my saws needed a MM or porting but it sure is nice to have the extra grunt and the awesome sound. I say add a dual port and make sure it gets tuned properly. Add the hd2 filter if you don't already have it. A dual port shouldn't void warranty if its tuned properly.
My 660 and 460 turn heads just like my Sierra with flowmaster 40 series. It's a disease:rock: Maybe a little cad but it doesn't stop at chainsaws for me.

Yes! I run Super 40's on all my trucks. Always turning heads. Especially the Z71 with headers and the "hi-flow" cats, a.k.a. hollow :)
 

Latest posts

Back
Top