660 muffler ? for Lake and the experts

[Ray Bennett]

I am finally getting around to opening up the muffler on my 660 which is the newer version with 1 small exhaust hole and no foam in the air filter. I have researched a lot of post on this subject but have a few questions. First can I get good results by simply opening the existing hole to .63 inches or will dual porting still be a lot better. If I must dual port it for best results what size should the holes be. Finally will I have to remove the limiter caps to richen the saw up enough with this minor mod?

Keep in mind I do not want to buy the factory dual port cover because in my opinion it is over priced and does not look good. I would prefer to keep the exhaust flowing 1 direction for felling purposes but If a Dual port will keep my saw running a little cooler and more powerful I will go that route. Thanks for the help.

 

[sILlogger]

i remove the baffle from within the muffler...the drill out the spotweld to the back w/o going all the way thru(this will save you some brazing/welding) and drill out the welds on the top of the baffle. remove baffle, weld/braze up holes. i open up my exhaust port to around 9/16". yes you will have to remove the limiter caps to richen the carb.

 

[Four Paws]

I am finally getting around to opening up the muffler on my 660 which is the newer version with 1 small exhaust hole and no foam in the air filter. I have researched a lot of post on this subject but have a few questions. First can I get good results by simply opening the existing hole to .63 inches or will dual porting still be a lot better. If I must dual port it for best results what size should the holes be. Finally will I have to remove the limiter caps to richen the saw up enough with this minor mod?

Keep in mind I do not want to buy the factory dual port cover because in my opinion it is over priced and does not look good. I would prefer to keep the exhaust flowing 1 direction for felling purposes but If a Dual port will keep my saw running a little cooler and more powerful I will go that route. Thanks for the help.

For a stock saw, somewhere around .875 - 1 sq. in. should be sufficient. Measure your exhaust port and multiply by .85 - that will give you the area of your muffler opening.

For a modified saw, it will be a good bit larger! I have gone all the way to 1.45 sq. in. on a warmed over 460 with great performance.

Josh

 

[Tree Sling'r]

I remove the baffle, match the muffler to the exhaust port opening, open up my stock port at least double. I then drill a hole on the other side (starter side) hone it out, put a screen and screw on a Husky exhaust shield, and then I add the ported Stihl face plate.
That would be my mod.

 

[2dogs]

Jared can you post an image? Sounds like a winner.

 

[Tree Sling'r]

Jared can you post an image? Sounds like a winner.

Me? Not Jared, but suppose I could get something posted later - if you were refering to my post of course.

 

[2dogs]

Me? Not Jared, but suppose I could get something posted later - if you were refering to my post of course.

Opps. Sorry. Yes I was talking to you though. Maybe Little Sling'r could video the entire job. (Hope I got that right)

 

[Tree Sling'r]

Not a 660, but a 460 muffler I just did for a saw today. The 460 baffles are a real pain, the 660s I don't have too much issue with

 

[OilHead]

Dont forget to order new limiter caps sence there arent any springs behind the needles on that model. The rebuild kit is very cheap now would be the time to attack it .

 

[2000ssm6]

Nice lookin' muff Sling'r

 

[sILlogger]

ok...ive searched in various methods and at differing angles...but does anyone know the part # for the screw in husky muffler defector?

 

[blsnelling]

My 361 muffler has a deflector on the left side like that.

 

[blsnelling]

I prefer to use spaghetti and measure the exhuast port itself, rather than the exhaust flange. Much more accurate. You'll want to go about 125% of the area of the exhaust port. On my ported 066, I needed right at 1 sq. in. That equaled out to 2 3/4" ID pipes. I use this calculator to figure the area. Calculator

 

[Dapper Dan]

I remove the baffle, match the muffler to the exhaust port opening, open up my stock port at least double. I then drill a hole on the other side (starter side) hone it out, put a screen and screw on a Husky exhaust shield, and then I add the ported Stihl face plate.
That would be my mod.

Yes...Husky part # please.. looks like a slick, no welding mod!

 

[blsnelling]

Yes...Husky part # please.. looks like a slick, no welding mod!

Husky PN 503 58 99 01

 

[Bowtie]

Brad, would you show us a pic of your 361 muffler mod? I dont care if Im derailing this thread or not, lol.

 

[blsnelling]

Here you go. My wife comes out in the garage a little while ago and says, "What are you doing?". Just taking a picture of a muffler for the guys on the forum This is a Dave Nieger muffler. As you can see, it has been split in half as well to get to the insides.

 

[Dapper Dan]

Nice!
Where did you get the screen? (SS?)

 

[blsnelling]

This is a Dave Nieger muffler.

I didn't do this one.

 

[Freakingstang]

Nice!
Where did you get the screen? (SS?)

same place you can get the scoop.


281/288 uses the bigger scoop


50/51/some 55's use a smaller one. (great for the 50-60cc saws)