True benefits of a muffler mod

It's a seemingly universal opinion that a muffler mod opens up the exhaust and improves performance quite a bit in most cases. Recent testing in the colossal MS261 thread actually showed the opposite on two different saws. I'd be curious to know how many here have actually done any scientific testing on an otherwise stock saw?


Could this be a placebo affect? I mean louder IS faster right?

I'll also note that I am fully aware that some saws respond better than others to muffler mods.

Diesel Pro said:

I'd be curious to know how many here have actually done any scientific testing on an otherwise stock saw?

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timberwolf did an excellent thread on an 260:

http://www.arboristsite.com/showthread.php?action=showpost&postid=53547

i would like to see the cant consistency problem in that thread resolved bf we start knocking MM. there may be some mufflers that don't benefit, but from what i have seen, it would be older models that don't have as much restriction. i think timberwolf did some studies showing the benefits of progressive MM on an 026.

nmurph said:

i would like to see the cant consistency problem in that thread resolved bf we start knocking MM. there may be some mufflers that don't benefit, but from what i have seen, it would be older models that don't have as much restriction. i think timberwolf did some studies showing the benefits of progressive MM on an 026.

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I agree on the cant consistency, but it sounds like the concensus is that the numbers are being trusted in that thread.

nmurph said:

i think timberwolf did some studies showing the benefits of progressive MM on an 026.

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Yes, I was looking for that one; couldn't find it...

Diesel Pro said:

It's a seemingly universal opinion that a muffler mod opens up the exhaust and improves performance quite a bit in most cases. Recent testing in the colossal MS261 thread actually showed the opposite on two different saws. I'd be curious to know how many here have actually done any scientific testing on an otherwise stock saw?


Could this be a placebo affect? I mean louder IS faster right?

I'll also note that I am fully aware that some saws respond better than others to muffler mods.

Click to expand...

Since there are only over 1,000 posts in that thread could you provide a link to or quote the posts?

I have noted and commented on the fact that virtually all the praises of "power enhancements" are at best measured by cookie cutting or "sounds louder".

huge gains on a CS400 Echo, cut time went from 15 second to 9 seconds with everything the same except for the muff mod and retuning. It was tuned good before the mod. I'd think saws with clogged up mufflers will have the most to gain. It wouldn't pay to mod the muffler on my 690 Solo, you can already drive a truck through it. Steve

Diesel Pro said:

Recent testing in the colossal MS261 thread actually showed the opposite on two different saws.

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I do not believe those results are typical, even with a 346. Something was definately flawed with that particular test.

On another note, I believe it to be a fact that a lot of people get the placebo affect, thinking a MM mod does more than it actually does. Sometimes it's not placebo and it does make a big difference.

gemniii said:

Since there are only over 1,000 posts in that thread could you provide a link to or quote the posts?

I have noted and commented on the fact that virtually all the praises of "power enhancements" are at best measured by cookie cutting or "sounds louder".

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Page 65 or so Edisto made some graphs which was GREATLY appreciated.

blsnelling said:

I do not believe those results are typical, even with a 346. Something was definately flawed with that particular test.

On another note, I believe it to be a fact that a lot of people get the placebo affect, thinking a MM mod does more than it actually does. Sometimes it's not placebo and it does make a big difference.

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That's kind of my point I just didn't want to make it 2,000 posts long in a couple of hours. I suppose I'm guilty of stirring the pot a bit here, but I think it needed to be said.

Anywho, good data will repeat...

A more consistent and preferrably larger cant should help in this regard. Make the average time longer so hopefully there is more variance in times between the stages of modifications.

Not counting the old saws (pre 1980) and the newer strato saws 15-25% improvment in cutting time seems to be quite normal (video and stop watch)with a fully opened muffler. On some saw with Cat mufflers or real choked up deals like the 359 and 361 seeing a 30% plus improvment is quite possible.

I'd like to take the time to redo some of those test, I could refine the data for sure with data logger running EGT, under plug temp and other thermo couples as well as getting actual in the wood RPM. Would be good to test some of the old arguments about muffler mods making a saw run cooler.

Diesel Pro said:

That's kind of my point I just didn't want to make it 2,000 posts long in a couple of hours. I suppose I'm guilty of stirring the pot a bit here, but I think it needed to be said.

Anywho, good data will repeat...

A more consistent and preferrably larger cant should help in this regard. Make the average time longer so hopefully there is more variance in times between the stages of modifications.

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IIRC, The MM had the 346 turning 15,300 at WOT. There's no way that cannot have a positive effect on cut times. If you took the slower times that I made, rather than the one cut that Andre made, the results would be much different. The gains from the MM would be huge. Testing with that wood was very frustrating. And the only reason I made those cants was to give the best test results possible, lol. So much for that idea!

blsnelling said:

I do not believe those results are typical, even with a 346. Something was definately flawed with that particular test.

On another note, I believe it to be a fact that a lot of people get the placebo affect, thinking a MM mod does more than it actually does. Sometimes it's not placebo and it does make a big difference.

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Well how much would it cost for AS members to chip in to buy you a dyno? Or if they are small enough to move easily, one that you major testers could pass around? I'd be good for $20 to start.

I have no idea what they cost, but the one Madsens depicts doesn't look that complicated.



/edit I am figuring over $1K probably
maybe you could sell share to have saws tested,

It is already sitting in my shop.

http://www.youtube.com/watch?v=fatrSgdW6hs

Just find that there are three things that stand in the way of progress; time, money and ambition. Getting two out of three is not hard but all three at once a bit of a trick.

So Brad,

I'm going to get a 261.

Should I do a muffler mod? If this is the only mod I do?

Thanks,
Marty

Sorry for my bs on your thread.

Kingsley said:

So Brad,

I'm going to get a 261.

Should I do a muffler mod? If this is the only mod I do?

Thanks,
Marty

Sorry for my bs on your thread.

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Absolutely.

Timberwolf - That's great - what do you have for results?

Do you have any numbers comparing a stock 660 w/ a stock 660 w/ a factory DP muffler? A woods port?
thanks

Bo yeah, the blunderbuss effect, louder is better right?? Short barreled rifles (carbines) are much more effective than rifles right? Revolvers looses a significant amount of exhaust gas between the cylinder and the frame thus generate a bigger bang than automatics. So, automatics are better weapons right?? A 22LR makes a much bigger blast out of a short barrel pistol than a 22short so the 22LR must be a more effective projectile when fired from that weapon right?? Now this should be fun…

timberwolf said:

It is already sitting in my shop.

http://www.youtube.com/watch?v=fatrSgdW6hs

Just find that there are three things that stand in the way of progress; time, money and ambition. Getting two out of three is not hard but all three at once a bit of a trick.

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Awesome and looks quite simple. THIS is what a guy needs as it should be able to plot the entire RPM curve and be repeatable. I don't have any vids and this is an old picture, but here is mine:






I now have a 10HP cooling fan in front of the trucks.

timberwolf said:

It is already sitting in my shop.

http://www.youtube.com/watch?v=fatrSgdW6hs

Just find that there are three things that stand in the way of progress; time, money and ambition. Getting two out of three is not hard but all three at once a bit of a trick.

Click to expand...

AWESOME!! i want one.