Explain Muffler Mods for MS362, Good Idea, Bad idea?

I was just curious, as I keep reading about muffler mods. Will a muffler mod alone, help wake a saw up? Does it shorten the life of the saw, or have other down sides? And what does it entail? Do you just drill a bunch of holes, and if so, any rules of thumb?

 

There are probably youtube videos of mm for this very saw to show you exactly how to do it. I have a 362 that took it beyond that; it was ported and it is a badboy, indeed. From years of reading posts, it seems that most any modern saw can benefit from a muffler mod. And, likely, retune it.

 

Muffin mods do “wake a saw up”. They also make em much louder so you have to weigh the reward. A more open and direct exit for hot exhaust gasses allow the heat out quicker. That’s a big benefit in itself. The carb more than likely will need a retune after you do it.

 

Take a stroll over to ope and see some great examples: Show off your muffler mods

 

Dont be afraid to open them up. Every saw I have has had the muffler done. The gains are well worth it.

 

I agree with above. I’m not really a fan of just drilling random holes, although I suppose it can work. Deflectors can be bought/made and are relatively inexpensive

 

Yep, I figured there was a little more to it then just drilling some holes.

 

I find it interesting that with 2 stroke OPE engines, the less restrictive exhaust the better...but in 2 stroke motorsports engines they will spend big bux on finely tuned exhaust pipes...and removing them removes power/performance.

 

Two strokes benefit from pulse timing in the exhaust system. It has to do with the way fuel air mixes and is charged into the cylinder and having the muffler hold the exhaust gas in, helps build more fuel gas in the combustion chamber. If it was straight piped or no muff or pipe at all. The fuel gas would blow out the exhaust port and build a positive charge in the piston. Kind of like sticking your thumb on the garden hose. You need just the right amount of restriction to make it work the best. 4 strokes have valves to do this so any restriction in the exhaust system is generally bad. That being said. I opened up my 362 and it helped. Obviously tune the high side of the carb to compensate.


Sent from my iPhone using Tapatalk

 

What for we have plenty of people right here that can do that. I am sure you have plenty you can show.

 

A few more.

 

Who else??

 

Will it help yes .. random holes.. bad idea
Good idea PM huskihl have him sell you a modded muffler bolt it on compare for yourself

 

Ok, that sounds like a good idea.

 

To see lots of pictures in a dedicated “show your muff mod” thread.

 

I thought this was a good video, because I’ve had a burning hand and melted plastic.

 

Scroll down a little and look at the jeweled bar on the one saw. Awesome looking. Tried to do that once on a old bar but didn't turn out very well.

 

Two of my saws have muffler mods, both benefited in performance with quick revving and faster in the cut. I modified them myself and removed the high jet limiter from the carb. The mods don't look pretty, but they worked well. The 250 is some louder than stock but not too bad. The 391 however requires ear protection. Both saws sound good. I'm out in the boonies and any neighbors that can hear them don't complain other than their saws don't sound that good... LOL

The 391 I used a dremel to cut slits along the strengthening ribs in the front of the muffler and pryed them open so the exhaust was directed downward. Big mistake. Two tanks of fuel and the oil tank below the muffler was starting to melt... I changed the louvers to direct the gas upward and was worried about getting exhaust in my face, but that hasn't been an issue at all. Lesson learned... I cleaned the tank off and put some metalized duct tape on the oil tank to reflect heat away from it. All good now. It runs great. I didn't mess with the original outlet and there was nothing to do internal to this muffler as there were no baffles inside it towards the front.





The 250 had an internal baffle tube with holes in it and I totally removed that then just opened up the output louvers with a screwdriver. It sounds good and performs very well. I think I had to open up the plate under the screen and output baffle. It's been a while since I did it and can't remember all the details other than all this was pretty easy to do.




Wow, looking at this picture I guess I should clean the spark arrestor screen... Hadn't noticed that before. Flash photography has benefits... LOL

The MS362 is new this spring and I figured on running it this summer stock and I'll do the MM on it this winter some evening. It has the fancy carb that adjusts itself so I shouldn't have to mess with it at all.