Muffler Mod...How Big is Too Big?

[5shot]

I added the Husky Deflector to my MS361 and then decided to go ahead and open it up to remove the baffle as well. It idles fine and runs well. I didn't really even need to adjust the H after removing the baffle...seemed to be running a bit rich (I used a tach).

I have a couple options to decrease the outlet already...I can put the flat spark screen on, which will reduce flow by 50%, and I also made a restricteor plate that goes under the deflector. It has 2, 5/16 holes that can be opened up if need be.

So...how big is too big? How do you know? What should I be looking for?

Thanks

 

[Canyon Angler]

I'm surprised you didn't need to fatten it up after opening up the muffler. Was it already modified? I had to richen up my 361 a good bit after the muffler mod.

 

[5shot]

I'm surprised you didn't need to fatten it up after opening up the muffler. Was it already modified? I had to richen up my 361 a good bit after the muffler mod.

I did richen it up after adding the Husky Deflector, but not after I took the baffle out.

 

[J D]

I've always aimed for around twice the size of the factory outlet (ie, a second hole the same or widening the hole proportionally... not double the diameter). Not sure how ideal that is but it's always worked well for me.
Matching the gasket & the exhaust inlet to the exhaust port can make a significant difference too.

 

[Jasent]

75% the exhaust port size is max from my experience. You won’t see any gains past that and it can actually hurt by causing the saw to want to run lean. You can fatten it up to compensate but you’ll just be blowing fuel out the exhaust. 60-75% has been best for me