359 muffler mod

[Coldfront]

Ok I took the cat muffler off a 359 etech cut it in half for 2 reasons to see what it looked like inside, and maybe gut it and salvage it. So in the mean time I ordered a oem 359 non epa muffler from Bailey's I thought maybe it would be similar to my 372xp muffler and just be totally hollow inside, no. It was exactly like the cat muffler I took off only the baffle plate dividing the muffler into 2 half's is just a steel plate and not the thicker cat material. It then has a exhaust outlet tube about a 1/2" ID. that goes from the front half behind the baffle and back through the baffle plate and out the muffler behind a deflector shield on the top of the muffler on the rear half. So without cutting this one open how should I try and modify it? I am thinking reach in the best I can through the exhaust inlet and cut the tube as close as I can to the exit outlet port but leave the tube at the outlet port the same size and leave the deflector as is only pry up the deflector to make the opening bigger, but it still only has a exhaust tube opening of 1/2". Then cut the tube off inside as far down the where it goes through the baffle plate as I can. Then I think I can reach inside with a small welding tip on a oxy acet. torch and cut a good portion of the baffle out by just melting it out. Then I also have another spare deflector plate that attaches with 2 screws and a spark screen I need to drill another outlet hole maybe 5/8"? and put the 2nd outlet port where on the muffler? Is it better to have the 2nd port exiting toward the bar side? The stock outlet is on the top to the left. It looks like the only 2 places I could add a 2nd port where the deflector will fit is the rear bar side or the opposite left side which may be too cramped. I wasn't going to mess with the oem outlet hole size because the deflector is welded on and looks nice the way it is. I don't want to mess up a new $50 with shipping muffler, after I pretty much butchered the cat muffler already.
I know there were a lot of old threads on this but all the pictures are now gone from the hack.

 

[Coldfront]

For anyone else wondering the 359 muffler # 504 70 64 01 that says non epa. Is identical to the cat muffler except the baffle is not the thick cat material. The baffle, the size of the holes, the tube, everything is the exact same as the cat muffler. It is not a easy mod.

 

[Big_Wood]

i do not have the patience to gut the baffle plate out of these mufflers anymore. just to much time for so little gain. what i did was cut a section of the muffler to fit a pipe, then i cut as much of the baffle as i can reach through the hole out. takes no time and once that is done i tac the pipe on, paint, and away i go. these are as close up as i got. the 357/359 saws have got to be one of the quietest saws i have ever heard with the stock muffler. it's just not right.

 

[sunfish]

I drill as many 3/8"-1/2" holes as I can through the baffle and add a second port. No need to cut the tube inside, or remove the baffle.

 

[Coldfront]

Well I just got done cutting the tube out and most of the baffle, it was fairly quick with a small welding / brazing torch tip. A lot quicker than trying to drill a bunch of holes. I just melted the steel away, Now I need to make a 2nd outlet hole.

 

[Coldfront]

I finished here are some pictures. The top port is oem the bar side port I just added. I cut out the inside baffle and tube, but left the top port opening oem except for prying open the deflector.

 

[sunfish]

That'll work, looks good.

Muff modded 359 is a great firewood saw!!!

 

[Bluefish]

I miss mine, sold it to a buddy who really needed it before CAD set in. Now I am prowling around for another. You are right, it was pretty quiet. Russ

 

[Coldfront]

They must have been quiet because of the maze and tube the exhaust gas had to go through before escaping. This mod should wake that saw up, I can't wait to try it out.

 

[Homelite410]

359 is the "low" hanging fruit of huskies.

 

[Coldfront]

359 is the "low" hanging fruit of huskies.

Maybe it was a lower priced saw in it's day, but we have 3 new Stihl MS311's at work and our old 359's beat the pants off of them considerably in side by side cuts both with new chains, and both totally stock saws.

 

[sunfish]

359 is a pro quality saw, same as a 357xp, but with a diff P&C.

I fixed up an old 359 for my brother, light porting, delete base gasket & MM. He couldn't believe the power out of such a small saw!

 

[Coldfront]

I got the 359 etech running last night with the new modified muffler, a new piston ring, and ground off the limiters on the high and low speed screws on carb. adjusted carb and cut some wood. All I can say is wow what a beast that saw is now. I did not do anything else no porting or did not even remove base gasket. That saw is a real screamer now. I'm afraid my 372xp is not going to used as much now except for really big wood. That 359 at over a pound lighter weight is probably going to be my go to saw for firewood now.

 

[sunfish]

Very under rated saw! I'd take a 359 over a 357xp and the xp is a fine saw too.

 

[cgraham1]

Very under rated saw! I'd take a 359 over a 357xp and the xp is a fine saw too.

I remember another thread where someone asked Mastermind what saw gained the most from being modded. And guess what the answer was? I've wanted one ever since.

 

[cory@owen]

They are fine saws before and after porting. Very good do all saw for firewood. Nice and small/lightweight.

 

[sunfish]

I remember another thread where someone asked Mastermind what saw gained the most from being modded. And guess what the answer was? I've wanted one ever since.

There's a new 359 in the trading post. I'd get it if I didn't have so much going on right now.

 

[Bluefish]

Working on a deal for a clean 359 with mild porting and the aftermarket muffler. Underrated saw for sure! Russ