Author Topic: Dual Port Muffler Experiments (Read 1882 times)

KilliansRedLeo · « **on:** May 13, 2014, 04:59:55 am »

Have been building up a few modified 372 mufflers to keep as stock using AM mufflers. I usually do the 288 outlet style. Out of the six I did, I did two using a tube out the bar side of the muffler similar to the one I did on a 362 recently. As I was doing these I was thinking about the diameter and length of the tube I used and wondering if anyone has experimented with changing the length of the tube protruding into the muffler or the overall length of the tube.

So I made up two with different lengths and varied the internal protrusion into the muffler and the external length, within reason. So has anyone else messed around with this and if so, what if anything did you learn. Or am I just daydreaming?

660magnum · « **Reply #1 on:** May 13, 2014, 07:52:52 am »

I've seen second outlets made this way.

A guy in the area has a 550XP with a tube outlet that extends almost all the way across the muffler on the inside.

This tube also had little perforated scoops inside like a car muffler.

KilliansRedLeo · « **Reply #2 on:** May 13, 2014, 10:07:22 am »

Jim, that is very interesting! Did you see/hear the saw run? Wondering about performance gain and noise level. I would like to come up with a performance increase while keeping the noise down. I've got a couple box mufflers left, if I can figure out a way to make the 'scoops' I'll give it a try. Did you happen to notice how far outside the muffler the pipe protruded?

660magnum · « **Reply #3 on:** May 13, 2014, 10:20:59 am »

This local guy and cut4fun and I all got together and ran my 550 and his 550 among other saws all with the same bar and chain.

The dual muffler modded 550 was noticeably faster than mine. But it could have been a difference in the age of the two chainsaws? There were some changes made in the 550XP's in the beginning. His is close to a year older than mine.

The guy didn't do his own muffler, he bought it from the Internet.

KilliansRedLeo · « **Reply #4 on:** May 13, 2014, 11:03:40 am »

Rats, It would have been nice to know what his thoughts were, if he had done the mods himself!

Cut4fun · « **Reply #5 on:** May 13, 2014, 01:26:43 pm »

I tested a pipe in a 066 cover that went across inside the front that the internet guy selling makes. The stock OEM DP cover for 066 flowed better.

I also tested a pipe in same config for a 084 cover and my simple caveman muffler mod with 288 deflector on cover out flowed piped one too.

My conclusion was my ported 066 and ported 084 ran better and had quicker cut times were made with oem or added deflector to cover over the pipes across the front cover.

To me the Ohio internet guy selling these piped covers for big bucks is.

084 simple caveman DP muffler cover mod.

084 muffler with pipe.

This is 044 046 cover. Sent me the wrong one. Digging for 066 piped cover which was better then stock, but not better then OEM DP or simple no cost muffler modding.

Cut4fun · « **Reply #6 on:** May 13, 2014, 01:37:41 pm »

Found it. I had actually cut some length off the outside to try and help it out. The stock DP muffler cover was way better then the pipe in ported 066.

660magnum · « **Reply #7 on:** May 13, 2014, 02:09:41 pm »

Quote from: KilliansRedLeo on May 13, 2014, 11:03:40 am

Rats, It would have been nice to know what his thoughts were, if he had done the mods himself!

Found it

Cut4fun . · « **Reply #8 on:** May 13, 2014, 02:13:46 pm »

Thats pretty neat how that one is done Jim. Has to be a different guy that did that one, is maker from NE Ohio?

The guy I got mine from in Ohio cut out the side part of pipe inside facing exhaust port on cylinder and installed spark screen way larger then oem screen.

660magnum · « **Reply #9 on:** May 13, 2014, 02:37:32 pm »

I was originally thinking Homelite410 made it but it was another guy "MX_Racer428" from Iowa? Jeff bought one example from him?

The pipe must be from some small engine muffler?

Notice the neat silver soldered connection

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Author Topic: Dual Port Muffler Experiments (Read 1882 times)

KilliansRedLeo

Dual Port Muffler Experiments

660magnum

Re: Dual Port Muffler Experiments

KilliansRedLeo

Re: Dual Port Muffler Experiments

660magnum

Re: Dual Port Muffler Experiments

KilliansRedLeo

Re: Dual Port Muffler Experiments

Cut4fun

Re: Dual Port Muffler Experiments

Cut4fun

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660magnum

Re: Dual Port Muffler Experiments

Cut4fun .

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660magnum

Re: Dual Port Muffler Experiments

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