performance exhaust

[Greenhorn]

Wonder if performance aftermarket exhaust for popular saws would sell? I'm not talking about those huge expansion chamber jobs - just factory replacement that flows better. No other machines get their factory exhaust tampered with as much as saws.

I put extra flowmaster stickers on my stihl stuff in hopes that one day I might have a baby flow on my 200!

 

[squisher]

It would have to be comparable gains and relatively inexpensive I'd think.

 

[SkwerI]

I'm not sure there would be much of a market. Those who understand small engines enough to appreciate the need for more airflow are fully capable of drilling a couple holes in the muffler and adjusting the carb. Those who aren't comfortable doing that are the same ones who won't buy an aftermarket exhaust if it "voids the warranty". Your only market will be the tiny number of people in between.

 

[Al Smith]

There are so many people attempting to sell modified exhausts at the present time I don't think there is room for any more.

Generally speaking most people who know anything about saws and use them on a day to day bassis have at least done some modifications themselves if only to remove the muffler screen.

 

[fallguy1960]

So is there any information or diagrams of what you are doing to the mufflers? I have a 51 husky that could use a little uumff. I also have a toy Poulan that needs help.

 

[GASoline71]

Stihl already makes the facory dual-port mufflers for the 046/460 and the 066/660. The one for the 046/460 will also fit the 044/440.

You can order them right at your local Stihl dealer.

The other saw brands I'm not sure about.

Gary

 

[fishhuntcutwood]

I'm not sure there would be much of a market. Those who understand small engines enough to appreciate the need for more airflow are fully capable of drilling a couple holes in the muffler and adjusting the carb. Those who aren't comfortable doing that are the same ones who won't buy an aftermarket exhaust if it "voids the warranty". Your only market will be the tiny number of people in between.

True dat. And there's a couple of outfits that already sell off-the-shelf muffler swaps; Walker's coming to mind.

 

[fishhuntcutwood]

So is there any information or diagrams of what you are doing to the mufflers? I have a 51 husky that could use a little uumff. I also have a toy Poulan that needs help.

I think I started at thread here about modding a 361 muffler, pic included. Try a quick search of the site, and you'll see discussion about opening various mufflers. Not much to it beyond some very basic metal work. Got a drill and a file?

 

[Greenhorn]

I think they'd be as popular as 2 chamber flows were on 5 liter stangs!

Just kidding. If the price was right and you could prove gains they might sell enough to pay for the fabrication. If they looked cool though......

 

[fishhuntcutwood]

If you can fab, sell and profit selling them at $30, because that's what a dual port front cover for a Stihl costs. I think Walker's sells ported mufflers for $40-$50 last time I checked.

Like Brian said though, most pros and those of us that mess with our saws, do it on our own with a drill and some basic metal bending.

You'd be selling to the guys that know they want a faster saw, but don't know how to do it themselves. These are the guys that, because they don't know what they're doing will cook a saw with an opened muffler.

But if I'm not mistaken, alot of tree guys aren't necessarily "saw" guys. They run saws for work, and that's about as far as it goes. Notable exceptions being Brian and Roger.

What do you have in mind? Porting stock mufflers, or building a muffler from the ground up?

 

[fallguy1960]

No luck finding that thread on the muffler modification for the 361. Maybe next week when my boy gets home we can figure it out he took small engine class in school.

 

[rumination]

I'm one of the professed minority that wants a faster saw but has next to no metal working skills. I might buy a modded muffler for thirty or forty bucks. I didn't realize that there are outfits that sold such things.

 

[squisher]

Once you crossover there's no turning back Leon. I had a 361 and a 660 professionally woods modded There's no going back.

Unbeleivable difference.

 

[rumination]

I'll get around to it one of these days, I'm sure. I've been thinking about sending my Husky 359 (don't laugh) to Ed Heard when I get back to the states. I hear a woods mod will perk that saw up fairly nicely.

 

[SkwerI]

It's as simple as making the muffler outlet hole almost as big as the exhaust port on the jug. Either make the original hole bigger or add a second hole. Then adjust the carb a little bit richer to compensate for the increased airflow. That's it, it's just that simple. Anybody can do it in 15 minutes. If you think there's more to it, then you're overcomplicating matters.

Now the woods porting is another matter altogether. That's the next big step up for even bigger gains. Well worth the $250 per saw cost IMO.

 

[squisher]

Heh I wouldn't laugh at no baby Husky wood eye?

Jk'ing that's who did my saws and I've probaby only got seven or eight tanks through the 361 and half a dozen through the 660 they're unbeleivable.

 

[rumination]

Brian, you underestimate my mechanical ineptitude.


I suppose that does sound doable, though. The 359 muffler has all sorts of baffles inside that should probably be cleaned out. How do you crack the muffler in half?

 

[GASoline71]

Muffler modded MS361... uses a Stihl TS400 cut-off saw spark screen...

It was done by a buddy of mine in Woodinville, WA...

Gary

 

[BostonBull]

ScottWojo makes a killing with these on Ebay.

Great idea but you may be a bit late to the table.

Try it and see how you do?

 

[fishhuntcutwood]

Muffler modded MS361... uses a Stihl TS400 cut-off saw spark screen...

It was done by a buddy of mine in Woodinville, WA...

Gary

I really like Andy's job. I'd have him do mine, if I hadn't already done mine.

No luck finding that thread on the muffler modification for the 361. Maybe next week when my boy gets home we can figure it out he took small engine class in school.

Yeah, that thread must be in the old House, and not here. But here's some pics-

I just drilled out the front (then vaccumed out the leftovers from inside of course), and riveted my 200T spark arrestor to the front of it.

And then a pic of a factory dual port front cover, which I also open up the hole on it, and the back half of the muffler as well. I'd say I probably add 30% to each hole, and that brings them both back in line to what they were back pre EPA. The one in the pic is before I opened the stock hole. It's bigger now, but still has the stock spark arrestor, and doesn't look like a hole you could park a boat in.

The 660 dual port cover is fine as it is IMO. I leave it alone.

 

[Al Smith]

Well,it's debatable weather to go the full cubic inch area of the exhaust port or ,like myself,about 85 percent. However I won't argue the point but will say this,if all you do is remove the screen and do nothing else you will normally see some gains in power . If you remove the internal baffles as well the gains will be higher.Hog one out to 85 percent or higher,hang on Sloopy.

A muffler tweek is the easiest way and cheapest to gain essentually free horse power. Don't go overboard though because that muffler is also needed in the system for the engine to work properly .There has to be about a zillion threads on about every forum on the net of how-to.

 

[fallguy1960]

Thanks for the input and pictures this will help. Now it looks like me and the kid have a project.

 

[GASoline71]

Cool fallguy! Let us know how it turns out!

Gary

 

[JIML]

Im worked on another new to me 660 today, its getting porting/piston work too. I added the dual port cover, enlarged the factory single port and added a third port on the other side. I spent part of the day building an arbor to mount the cylinder in my lathe so I can cut the base down.

 

[hugashe]

361

just put mod on my new 361. wow is all i have to say.