Chainsaw Modifications

[titan]

Anybody on board here ever done any mods(porting,muffler mods) to their saws?I'm curious as to wether modding an already good saw is worthwhile.....are they safe to do?I'm not concerned with voiding my warranty(what little you can get),I just want my saw to perform to its full capacity;if a diy muffler mod will give me a bit more "jam" while in the cut,then I'd like to try it.What are your experiences and beliefs?

 

[minesmoria]

I have a husky 372xp 28" bar and got my muffler done by walkers saw shop. The cost was only $30 which give's an extra 1/2 hp and the engine runs way cooler less heat to the engine!

 

[titan]

Sounds good,I'll have to check and see if any local saw shops would do it ,although I'd like to tackle it myself......if I could find out the proper way to do so.

 

[cmonSTART]

Interesting. What exactly did they do to the muffler?

 

[Soopah 27]

You may want to check out the arborist site. There's a section on saw mods there.


http://www.arboristsite.com/index.php

 

[olive wood]

......or find the hardcore saw people here -
(broken link removed to http://www.chainsawperformance.com/forumdisplay.php?f=3)

 

[sedanman]

I have a 361 that's ported by Ed Herd, along with a Dolmar 7900 he did and a Husky 2100 he did. I am going to have my Dolmar 5100 done by him as well. I have done a few muffler mods and they do give measureable improvements. Ed can be found on chainsawperformanc.com My 79cc Dolmar 7900 will outcut a 92cc Stihl 066 any day of the week, the 100cc Husky is a pure animal that is absolutely UNSTOPABLE with a 28" bar on it.

 

[computeruser]

I have a 361 that's ported by Ed Herd, along with a Dolmar 7900 he did and a Husky 2100 he did. I am going to have my Dolmar 5100 done by him as well. I have done a few muffler mods and they do give measureable improvements. Ed can be found on chainsawperformanc.com My 79cc Dolmar 7900 will outcut a 92cc Stihl 066 any day of the week, the 100cc Husky is a pure animal that is absolutely UNSTOPABLE with a 28" bar on it.

Have you had the 7900 apart post-EHP? Did he get this gain with or without finger/boost ports?




To answer the original post, simply opening the muffler up on a modern saw will yield nice gains in power, acceleration, and in reducing engine temps. Those with cat converter mufflers are well advised to ditch the cat muffler for a non-cat and mod that one. The only saws I have in stock form are my Husqvarna 238 and 154, everything else has been muffler modded.

 

[titan]

computeruser, what's the proper way to open up a muffler?......remove the baffle and/or drill holes in the housing?I want to go ahead but don't want to "over do" it.

 

[Lignums]

After taking the advice of posts above, I went to those sites and looked up muffler mods and from what I gather from many, many threads state that 85% is the rule of thumb. Keep the exhaust port opening 15% of total size of muffler. On my old 028 Super, I just used an 1/8'' drill bit and drilled a series of holes in the front of the muffler in the shape of a circle, about the diameter of a nickel. I do not have a welder, or know a friend that has one ready so that is the way I went with it. After I tested it out, there was a noticeable difference in the way it ran; way faster and obviously louder. I will have to adjust the jets, as I did notice that the 4 cycling that I had before is gone, and I do not want to lock up is saw. Most pictures of mods I seen have a piece of pipe about 1/2" welded either into the front, or side of the muffler. Some looked hillbilly, others looked factory. I seen enough improvement, that I will adjust the muffler on my 455. That saw runs allot hotter that the 028's I have, so hopefully this will help out, and get some more performance out of it.

 

[rdrcr56]

Don't forget to match the opening in the muffler to the gasket