Open up MS440 muffler outlet

Recently talk of old 044s and new 044s and 440s mufflers I decided to show opening one up. I did this to a couple already and it really changes the saw for the good.
First an old angle fin 044 outlet.
Now a later model restricted outlet.
Big difference in the two.
Now bend tabs and pull out screen.

 

Fortunately I have access to a lot of cool tools at work so I got out the angle air powered grinder and a carbide burr. I went on the outside first then on the inside to get way down in there.
And here is the finished result. Looks ok to me. Run the saw a little bit and the soot will cover up the shine.

 

One last thing is to put back spark screen.
Don't forget to bend tab.

 

Ya I was like the chainsaw whisperer when I did that. The tree guy was shocked how good it ran after.
I'm not even sure I'd call it s muffler mod either since I only opened up to the old school dimension.

 

I do the same thing. To add to your post. If your lucky to get one with no cage that is all that is needed. If you get a back half on a stihl with the cage in back half there is more to do to help. Remove cage or drill it full of holes.

I do like adding the DP covers to the 044 046 066 also.

 

Before and after on a 036 rebuild.

 

plus one on the crazy part... I picked up a 2010 model year 460 last week from a tree service, I started it up and it sure sounds all choked up!

Looking at the hole, I dont even know how it runs...

 

I will, all in due time. Have to order a few parts for the saw before it will be in service. It's going to breath for sure

 

maulhead, Put a DP cover on it oem or aftermarket while you are at it IMO. Pic is the complete muffler set I like from raisinman brand. Been using them on 044 046. Can get them with or without the front screen.

 

I too used to use the 1/4" die grinders and burrs for this. Then, xskier turned me on to this; http://www.amazon.com/Astro-Pneumat...32044500&sr=8-1&keywords=astro+pencil+grinder

I picked up some 1/8" double cut burrs and life has been great ever since!

 

Hey, what is the old-school diameter, exactly?

 

I will have to measure it when i get to work tomorrow. The saw is on my bench there.

 

Sorry for the delay Jon. It's .7 inches. I'm not real precise but that's close.

 

Thanks!

 

I've got a MS460 to work on and looked at muffler outlet, then opened it up!
Before pic. Opening was about 5/16.

After pic. I opened it up to 9/16.

I'll bet the dudes happy when he gets it back.