The Moody 362 C-M

[WoodChuck'r]

 

[richard t]

Stihl and husky are both flimsy anyways opcorn:

 

[blsnelling]

I've been talking engines to people for over 40 years and I guess I just presumed that when I used the word torque everyone understood what I was talking about. Of course every engine has both HP & TQ, but generally when you refer to engines built for TQ, you are referring to a broader power band at lower RPMs. When you build an engine for maximum HP, it usually has a narrow power band and peak HP at high RPMs. Forgive me for presuming that everyone understood the difference. It is the difference between a racing saw and a wood port (everyday working saw). What works for one does not work for the other.

And I know that saws operate a WOT, but maximum RPMS are generally around 14,000 and in the wood they usually drop to about 9,000. That is when torque becomes important.

You can find some very good references to the difference from some very experienced people in the current thread "Ported 70 cc Work Saws".

Every engine performs best when all of the parts work in conjunction with each other. In another thread a guy put the stock muffler back on a ported saw and found that it rapidly built up excessive heat. That is because a stock muffler is not adequate for the volume of gasses a ported saw can flow.

The reason muffler porting on a stock saw is usually effective is because the EPA forces the manufactures to back up the exhaust gases so they will continue to burn more completely. The example that Windthrown gave of Stihl developing the duel port muffler covers for the 046 and 066, which increased power but were banned by the EPA, is an excellent example of this.

If a saw did not need any back pressure at all to function properly, racing saws would not have any muffler on them and woods ported saws would have racing style mufflers on them. There are reasons, related to saw performance, why they don't. I think most saw builders adhere to these parameters even if they think I am wrong. Have you ever noticed that you have never seen any engine, 2 cycle, 4 cycle racing or otherwise that does not have some sort of exhaust manifold or header on it? A lot of research goes into matching the exhaust manifold to the intended use of the engine.

I usually stand by what I say because I do my research. I have learned a tremendous amount since I joined AS. That does not make me an expert, but I am no dummy either.

Also, for the record, I do understand what the 80% relates to, go calculate it for yourself. All of the information is posted on this thread.

Also, for the Record, I think KG's saw sounds stronger than Moody's, and it is not ported (this is admittedly just an informal observation).

Hope everyone has a good evening.

Enough of your condescending, self inflating mumbo jumbo. Are you trying to convince us, or yourself?

Let's get a couple things straight. As with most guys like you, you like to twist things and change them to fit your argument.

1. This argument isn't about whether or not you can go too far with a MM. It's ALL about you implying that opening it too far could slow it down. I don't care if the original numbers were right or wrong. I'm talking about your implication being wrong. Opening the muffler 200% is not going to slow the saw down in the cut, period.
2. For the record, I'm not a fan of excessive exhaust opening on a work saw. After a certain point, you're making more noise than power.
3. Keep it simple. Don't over think a MM. All you often need to do is open up the existing port, as much as the deflector will cover. If you want more, GO FOR IT! It's your saw. Do what you like with it. Yeah, it's going to get louder. Maybe that's what you want. But know this...it's not going to make it slower.

 

[stihl sawing]

Stihl and husky are both flimsy anyways opcorn:

Well now that we've got that all cleared up....Old Poulans and Macs rule.

 

[richard t]

Well now that we've got that all cleared up....Old Poulans and Macs rule.

Yep

 

[redfin]

A good runnig 70-90cc saw will turn 10-11k in the wood. If it won't I'll work on something else on it to change that.

Timberwolf tested the muffler openings in 2006 or so. An 026 lost no cut time all the way to an absurd opening size. Idle mad throttle response did suffer. I usually make 2 outlets at 5/8"x3/4-7/8" on the larger saws.

Crap like this is why this site has gone so far down hill. It's drove away the more knowledgeable folks and left new people that haven't tried any of this stuff out for theirselves.

I found this to be true myself. My 026 was the first saw I did a mm on. I miscalculated the first time around (180%) and ended up with very poor throttle response. I closed it down to roughly 120% and all is well. There was no loss of power between the two muffler openings.

 

[angelo c]

do we have a "jump the shark" smiley ?

we clearly have passed the "adding value" to this thread and have no entered the "pi55ing match" stage....I nominate thread close.

 

[nmurph]

do we have a "jump the shark" smiley ?

we clearly have passed the "adding value" to this thread and have no entered the "pi55ing match" stage....I nominate thread close.

Don't look now, but the Mets are in third place in their division.

How 'bout that grand salami last night?????? Talking about getting up off the carpet when you've been punched in the mouth!!!!

 

[chadihman]

Please, no empirical data.

?????? Explain please. I'm not the brightest bulb in the case. Not comparable data?

 

[ash man]

Someone needed to tell mm the truth. Hopefully he will take Brads advise as constructive criticism.

 

[nmurph]

?????? Explain please. I'm not the brightest bulb in the case. Not comparable data?

You couldn't see the tongue firmly ensconced in the side of my cheek??

 

[MacLaren]

Don't look now, but the Mets are in third place in their division.

How 'bout that grand salami last night?????? Talking about getting up off the carpet when you've been punched in the mouth!!!!

Couldn't of happened to a better guy either. Danny Uggla really needed that two Homer game last night. Go Braves.

 

[MustangMike]

I haven't seen any variable outlet mufflers yet. I'm going to scratch some time up to make a test muffler for testing a MS 460 and a MS 461. I'm also gutting a 361 muffler so I'll test that to.

I would love to see the results of your tests. It would be great to see the both the cookie cutter times, and what happens when you put a load on the saw.

Perhaps you will teach my stubborn A** something.

Thanks.

 

[nmurph]

...Perhaps you will teach my stubborn A** something...Thanks.

Doubtful. Died in the wool, devout Stihl-heads are usually so bc they refuse to see anyone's opinion but their own. That may or may not apply to you.

 

[KG441c]

Tired of this mess! Ill be glad when an established Porter starts a 362c go through the saw thread

 

[MustangMike]

On saws probably not. But 2T sea doo and 4T yamaha sleds have variable exhaust volume systems. There must be something to it, but those two systems are designed for better part throttle performance.

Mustangmike, you're an old hot rodder. What do you think about selectable exhaust dumps. Do they make the car slower in loud mode?

I may be green on chainsaws, but cars I do know about. Generally opening dumps, or opening the headers will add power because the exhaust is overly restricted to keep the car reasonably quiet. Of course you have to adjust engine timing accordingly or you may suffer a loss in power instead of a gain.

That said, the benefits are not unlimited. If you put large tube headers or 3" duel exhaust pipes on a stock engine that does not need that capacity driveability and low and midrange torque will suffer. Your exhaust should be matched to your engine based on cubic inches, carb, cam, etc.

If you look at HP and TQ curves of an engine you will notice that peak HP generally is at a high RPM and peak torque at a much lower RPM. Therefore, it is very possible to increase peak HP while simultaneously lowering peak torque. As RPMs increase, you don't need as much torque to generate the HP.

For example, a centrifugal supercharger or a turbo generally will produce the most peak HP (at high RPMs), while a Roots or Twin Screw SC will produce more peak torque and a far broader powerband, but peak HP will be lower.

As I previously stated, if you go to the current thread "Ported 70 cc Work Saws" you will see some very experienced members talking about this.

 

[bryanr2]

Tired of this mess! Ill be glad when an established Porter starts a 362c go through the saw thread

+1 if you Mike or Dex dont send MM yours- I might have to buy one for the sake of AS.

 

[MustangMike]

Doubtful. Died in the wool, devout Stihl-heads are usually so bc they refuse to see anyone's opinion but their own. That may or may not apply to you.

I am stubborn, but I am not stupid. I do like to see the evidence. FYI, there are also a lot of Orange supports that make unsubstantiated comments all the time, and no one calls them on it. I also like to apply my auto engine knowledge to chainsaws, but that (admittedly) does not always work.

Hopefully, in the end, we all learn something.

 

[MustangMike]

Yep

View attachment 344489

That is wild looking, thanks for posting it.

 

[Trx250r180]

I am stubborn, but I am not stupid. I do like to see the evidence. FYI, there are also a lot of Orange supports that make unsubstantiated comments all the time, and no one calls them on it. I also like to apply my auto engine knowledge to chainsaws, but that (admittedly) does not always work.

Hopefully, in the end, we all learn something.

Mike ,these little 2 stroke saws respond different to mods then cars do ,but they pump air in and out like anything else ,pump more air ,get more power is a simple way i can describe it ,a lot of loggers around here run triple ports on the saws ,there must be a reason besides the noise it makes