Stihl 038 Super mufler mod...do or don't?

[hawcer]

I'm thinking of modding the muffler on my 038 super. I had it off and apart yesterday to take a look inside. It has a square cage in front of the cylinder exhaust port that has holes on top, bottom and sides. The front cover has a small baffle on interior of the exit side and it has two slots on the outside for the exhaust to exit through.(chain side)

Anyone modded a muffler like this? Not enough gain to be worth it? The 026 was pretty straight foward and I found many pics and info on doing it here....just not sure on the 038 AVS.

 

[Saw Dr.]

Mufflers are pretty free on those already. Can't hurt to remove the cage, though. Just make sure to leave the flange intact in the back. Otherwise, the thin metal of the muffler will distort and leak at the gasket.

 

[cajunhillbilly]

Why not. Almost every saw I have running I have done a mm or will do soon. Only a couple of hours work for a huge gain, maybe not so huge on an older saw, IMO. Be sure to richen the carb a little before starting it up and re-adjust after.

 

[hawcer]

So the cage does nothing and can be (almost) completely removed?

Any modding needed on the baffle...does it need opened up or just open up or add to the exit ports?

My muffler looks to be like the one second down from the left in this pic I found on here.

View attachment 219371

Also, my muffler has no screen in it and doesn't have a place for a screen...If I am to mod it with anything more than adding a exit vent or two,like an exit pipe, should I put a screen in it?

 

[Saw Dr.]

Don't over-think it. Just carefully remove the cage at the muffler inlet, open the outlets to what you want, and go cut wood. The only time you'd have a problem (about the screen) is if you are cutting on government land. Tons of saws here running no arrestor without an issue.

 

[hawcer]

So, all I need to do is:

1) remove cage
2) open up or add exhaust exit ports
3) retune
4) go cut wood

I don't want to do anything to the baffle over the exit ports?

 

[Saw Dr.]

Modding mufflers is an individual art form. There are hundreds of ways to get it done, and no official "right" way to do it. Open the outlet as much as you feel comfortable and give it a try. It is always easier to remove more material than to put it back. There will be a point were more area gives no more gains (except maybe in noise levels.)

 

[Sport Faller]

Mufflers are pretty free on those already. Can't hurt to remove the cage, though. Just make sure to leave the flange intact in the back. Otherwise, the thin metal of the muffler will distort and leak at the gasket.

Yessir, my only saw that doesn't have a MM is my 38 MagII, I cut the cage out but I'm not sure that there's a whole helluva lot to gain over the already triple ported factory muffler LOL

 

[hawcer]

I'm trying not to overthink this....but overthinking is a bad habit I have.

If I go the "weld in exit pipe route" will there still need to be some sort of baffle in the muffler or does the pipe exit directly from the main muffler chamber?

None of this probably needs to be done...but when it comes to adding character and a little personal touch, I'm all for it. I'm the type that can never leave anything alone...

 

[Mad Professor]

You seem to have a single port muffler so adding an extra port will wake things up.

With the dual ports I just open up the existing port as large as possible while still retaining the screens. The baffle gets hogged out with bigger/more holes or removed.

As mentioned, the 3 port factory is pretty open all ready (bottom right on your IPL)

 

[blsnelling]

You can completely remove the baffle where you end up with just an empty can.

 

[Saw Dr.]

You can completely remove the baffle where you end up with just an empty can.

That is what I would do. The factory triple port muffler has two ports on the back-shell, and one in the front. Those back shells are getting pretty rare, and you can do the same with a Husky 288 deflector.