365 Dual Port

[PetrolHead]

Not to give anyone a big head, but I really liked the 372 muffler mod done by Bwalker some time ago.
Finally had some time to try it for myself, on this one I cut and shut the front roof of the muffler to allow the front port to sit lower than the rear one. This also allowed the front port to sit more central making the screen easier to locate. Using pot belly black for the paint which means 16 hours between coats, so I won't be able to fit it for another day (wife won't let me bake it in the oven)
If anyone is interested I can post another pic when it's fitted to the saw with the screens in place.
Really enjoyed doing the mod.

Here's some pic's
View attachment 33067
View attachment 33068

 

[woodfarmer]

thats some nice work, if you wern't so far away i'd have you do mine

 

[Simonizer]

Not to give anyone a big head, but I really liked the 372 muffler mod done by Bwalker some time ago.
Finally had some time to try it for myself, on this one I cut and shut the front roof of the muffler to allow the front port to sit lower than the rear one. This also allowed the front port to sit more central making the screen easier to locate. Using pot belly black for the paint which means 16 hours between coats, so I won't be able to fit it for another day (wife won't let me bake it in the oven)
If anyone is interested I can post another pic when it's fitted to the saw with the screens in place.
Really enjoyed doing the mod.

Here's some pic's
View attachment 33067
View attachment 33068

I didn't ever think I would say this on AS, but,...nice job. You obviously care about your work. Well done.

 

[04ultra]

I didn't ever think I would say this on AS, but,...nice job. You obviously care about your work. Well done.

Simon do you feel ok??? is there a Doctor in the house...

For the record this is an AS first for Simon ..

BTW nice muffler PetrolHead

 

[Simonizer]

Simon do you feel ok??? is there a Doctor in the house...

For the record this is an AS first for Simon ..

BTW nice muffler PetrolHead

I am fussy Ultra. I give credit where credit is due. It looks like he cared about what he was doing and that is simply the difference between wannabe's and tradesmen in any vocation.

 

[PetrolHead]

Thanks to all for the comments.
What I appreciate is that most of the know how is already contained within this one site. Did a search for "muffler mod" and spent most of the evening reading and even had pics to detail the instructions, fantastic!
I asked young Einstein in the next room if he could stop playing computer games long enough to help me with calculating areas for the port. He did! came out an hour later with a graph so I could plot what size I needed. All I had to do was grab a coffee, get the daughter to make me some toasted sandwiches and locked myself in the shed. Was great fun, can't wait to fire it up tomorrow morning and have a day out cutting next Saturday.
Thanks to all for the great info.

 

[pbtree]

Dude, that is one heck of a fine muffler mod. I would like some follow up feedback on the results on the saw...

 

[PetrolHead]

Hurry up & dry!
View attachment 33100

 

[PetrolHead]

Man I'm tired, I cut with the saw all day.
Results of the mod :

Starts the same
Idles the same
Hasn't changed it into a bigger capacity saw

Sounds nice, has a bark now but not much louder at all
Real nice in the cut, that's what I noticed the most. Just made a nice saw even nicer.

The paint even stayed on for now. Carb was checked but left alone because it was on the rich side already, nice burble out of the cut and the tach showed 12700 which seems to be right where it likes it.

Was it worth the effort? For sure, I will do it again if needed.

 

[bwalker]

I dont know about the 365, but the 372 is much happier at just under 14,000.
NIce job btw.
As for performance. The only thing that I have to add is that maybe mine works well because it isnt screened. If you are going to add screens you may have to add port area..

 

[Toneman]

Looks great! Nice work!!

 

[stevieb]

Well done dude!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Freakingstang]

I dont know about the 365, but the 372 is much happier at just under 14,000.
NIce job btw.
As for performance. The only thing that I have to add is that maybe mine works well because it isnt screened. If you are going to add screens you may have to add port area..

Ben there is a 1000 rpm difference in the 365 to the 372 (husky rated specs). Some of the 365's are a closed transfer and some are open..

Of mine, both were closed ports, and they didn't like anymore than 12,800. I tried more, but it doesn't fair well.

After working with a few 372's, I opened up a 365 jug to the 372 spec transfers and it is a differant saw. (all other ports left alone, just widened the transfers(at cylinder entry, and opened lowers) to the same size as a stock 372). These things are really choked back from the factory. Mine with that setup liked 13,950-14K And wasn't far behind a stock 372. With a little port work in the exhaust and intake area, the 365 is a respectable saw that will hand a stock 372 its' ass.


-Steve


BTW, Nice looking muffler mod.

 

[PetrolHead]

Point taken about the screens Ben. I pondered over the question for a while before the mod. The screens are both removable, so I can take them out if I ever want to try without. Total outlet was about 70% of exhaust port Before the screens are fitted, main thing was that with screens in or out it's still twice the outlet area than standard.
It really showed true colours today because we were in cleaner & bigger wood than yesterday, has gained power in the cut for sure.