Homeowner saw muffler mod

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Gunsling3r1988

Newbie chainsaw addict
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King, NC
I was considering a muffler mod for my Husqvarna 440, not so much for more power, though that would be nice, but to help it run cooler. Is it worth doing a muffler mod on a homeowner saw?
 
I dont know how choked down a husky 440 muffler is. But on a stihl 029 290 you can see gains of 18%-23% just on a simple 30 min muffler mod on them.

I just did a free no cost gill one on my stock 359 I got on trade. Open baffle in middle in couple more spots inside and gilled the side.
 

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Had a little old Husqvarna, maybe a 140? Had a cat converter muffler. I gutted it and I'm sure it ran better and cooler. It couldn't do otherwise.
 
I have both a 435 and 440 that I have muffler modded and retuned. It will make a small but noticeable difference. The cans on these saws are already open, so just doing a little gasket and port matching and then opening up the outlet with some Dremel work is quick and easy. If you want to get fancier, you can sart drilling big holes, brazing on outlet pipes or buying premade opened mufflers. I just opened up the stock outlet and put some heat reflective tape on the plastic parts above the outlet. Depending on the vintage of your saw and the carb used, retuning may be simple or a real pain to get the right splined tool, which was the case with my newish 440. I ended up having to buy a few from England.
 
However you mod it, make sure you get it cleaned out really well. Any metal chips or abrasive debris can get sucked back into the engine. On one muffler they was crimped together I filed the crimped edge to open it so that it could be cleaned out. Then welded back together.
 
However you mod it, make sure you get it cleaned out really well. Any metal chips or abrasive debris can get sucked back into the engine. On one muffler they was crimped together I filed the crimped edge to open it so that it could be cleaned out. Then welded back together.

If I was to mid mine, I would take it to someone that knew what they were doing.
 
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