Thread: Is it possible, muff mod w/o increase DB level?

Did my 335 muff recently. I love getting an 20%+ ? increase in HP and cooler running to boot.

But is it possible to do a muff mod w/o increasing the DB level?

I'd like to protect what hearing I've got left. I know, I know, put out the ear muffs.

Could be done? You would think if it was possible, saw mfgs would already be doing it? :Monkey:

Yes, the person who could design a muffler that would flow better without increasing the noise level (and within size and weight constraints) would likely be fought-over by the chainsaw manufacturers.  But I fear noise levels (OSHA) are only a part of the equation.  Without keeping the exhaust trapped and hot long enough, I suspect the EPA will not be happy.

Ever notice the lack of chainsaw manufacturing engineers on this site?  Does anybody here know any of them?  Sure would be nice to have some interaction with them.

Glen

Two stroke motorcycles have been increasing HP within EPA limits for years. but that's probably not a valid comparison,

You would think more saw mfgs/engineers would use feedback from this forum.

One easy way is putting a pipe muffler on it. The type of thing saw builders like Dennis and KD will oput on a racing saw. Those things are clumsy though for a woods saw, so I don't think many people do it that way.

Pictures and/or links please.

Originally posted by 046


I'd like to protect what hearing I've got left. I know, I know, put out the ear muffs.

AND the ear-plugs!

I love these nasty smelly gasoline engines.

The performance and longivity gains are starting by just opening up the muffler and tuning the mixture.

You would think that the factory would be interested in getting max HP & longivity. Maybe not, they get to sell more units if they die earlier.

Leaving the mfg out of this, if it's possible to get HP increase @ a decent DB level, then why not.

Why not?

The answer to that can't really ignore what the manufacturers are doing.

First, they're not doing it to increase frequency of sales.  Do you think they like having to look bad by producing saws which don't last as long?  No, the fault lies fully at the feet of the EPA and OSHA (in the US) and similar agencies worldwide.  Two-stroke engines have distinct advantages via less complexity and lighter weight, all while producing more power per time frame.  But they also pollute more than their 4-stroke-cycle counterparts.

Our servants in government take the role of masters and force things down our throats all the time.  Much, much too often.  We can't have our saws be loud because that will harm us when we use them.  Now vibration is entering the regulated scene as well.

We can't have unburned hydrocarbons being emitted into the air we breathe, especially while cutting down the trees that do most of the work cleaning that air.  So the mufflers must retain enough heat to ensure the wasteful two-sroke-cycle engines pollute the least amount possible.

I don't believe you can be fined for operating your modified EPA-regulated chainsaw in your own yard, but you cannot legally operate it on Federal (and likely State) property, and your mechanic can be fined for working on it without restoring it to approved configuration.  Practical reasons for "why not?"?

Probably nobody here will complain about equipment becoming lighter, more fuel-efficient, and vibration-free.  Perhaps in time a method will be put into place whereby saws can once again breathe better while remaining both quiet and emissions-compliant.  I've heard about reed valves in the transfers (see the bolt-on covers on Huskies, which are probably for production and emissions purposes) through which a shot of straight air precedes the fuel charge, so the portion which escapes out the exhaust port before it closes will not contain raw fuel, but only air.  Time will tell if that and/or other schemes will solve the problem.

Glen

Thanks for the detailed explaination. I had not factored keeping the muffler hot enough to burnoff the unburned fuel in the exiting exhaust. And now vibrations???

So the EPA has a heavier hand in this proccess than I thought.

I guess, to make saws compliant they are ran lean as possible.

In auto technology it's acomplished with a catalitic converter. that doesn't look like an option. But that never was my original question.

I only wanted to know if it's possible to get the extra flow and keep the DB down. Thank goodness, I not required to meet EPA requirements on my equipment.

enjoy it while it last.. they gonna be regulating what brand o cereal u eat for breakfast ,,before these nuts are done..
i mite have to find me another planet ..