Custom exhaust tinkering

[jasent]

Been playing with different exhaust ideas and figured I’d share. Saw is my favorite jonsered 2094. Never liked the factory exhaust and even with a healthy gut and muffler mod it seemed it was holding it back. So I started tinkering.
first exhaust was simple pipe but was way too open. She leaned out fast and saw hated it.

 

[jasent]

I tried capping it and gain a little back pressure but that failed as well. So I scraped that pipe and started a new one. This one has good flow, back pressure and is ugly as all hell. Saw loves it. I call it the tea pot

 

[Labfab]

I play with exhaust as often as possible, some saws like more than others is about the only helpful information I can offer. Which is about no help whatsoever.

 

[jasent]

I play with exhaust as often as possible, some saws like more than others is about the only helpful information I can offer. Which is about no help whatsoever.
I’m going to keep tinkering with it till I find a design both me and the saw loves. Then I’ll switch to a different saw and learn some more! I want a good muffler that’s not huge. Work saw style

 

[Labfab]

I play with exhaust as often as possible, some saws like more than others is about the only helpful information I can offer. Which is about no help whatsoever.
I’m going to keep tinkering with it till I find a design both me and the saw loves. Then I’ll switch to a different saw and learn some more! I want a good muffler that’s not huge. Work saw style

You get a better feel of what each saw will like the more saws you deal with. There is a point where it comes to just blowing fuel out the exhaust with no power gains, so be mindful of that. Just my personal experiences as I usually do things to have first-hand experience rather than what everyone says.

 

[BayouCountryPowerSaws]

I've actually been reading on two stroke exhaust and theory a lot here lately. I can share with you what I know. Keep in mind that we are dealing with much smaller volumes of air fuel in power saws.

A strait pipe creates a pulse that helps pull the exhaust gasses out of the cylinder.

A megaphone or a pipe with a divergent flare at the end creates a second pressure wave that creates a strong enough pull that it can pull from the crankcase through the transfers. This in most cases can be too much because the case pressures are higher in a power saw in relation to bore and stroke than a bike. That's where the tuned pipe was born because the divergent cone pulls it from the case and the convergent cone at the end stuffs the fuel back into the cylinder as the piston closes at a certain rpm.

Buckins Bearclaw mufflers help pull the exhaust gases from the cylinder and that's why they run so well. But you have to keep in mind diameter and length because that determines its effectiveness at different rpm ranges.

Hope this helps!

 

[jasent]

What I want is a good work saw design. I don’t build hot saws I build work saws which is why I don’t want tuned pipes. I’ll check out buckins bear claw muffler design, thank you for the info.

 

[BayouCountryPowerSaws]

If you want something that's going to be better for a work saw, I pipe isn't a bad place to start, you just don't want it to open that it pulls too hard and you end up loosing too much out the exhaust, I would start at somewhere around the diameter of the exhaust port because if you increase the size anywhere that is a divergent cone and will cause the pipe to pull harder.

 

[jasent]

The tea pot muffler is same size as exhaust port for 1” or so then dumps out about 1/2” inside the cone you see on the outside. Then the exit pipe is about 75% the port size.

 

[WhAt miX shOuld I?]

I build a lot of poulan counter vibes and craftsman clamshell saws and stock to mildly ported, I remove the spark arrestor, drill the diffuser holes to 17/64" and open/reshaped the outlet slightly. It doesn't gain any noticeable rpm, but they pull much harder and sound like an actual saw.

 

[jasent]

Dropped this heavy leaner today. Nice long straight trunk with very little taper. Will use this log for future exhaust testing

was going to get a base line for my husky 51 before starting exhaust work. But it needs a carb kit as I cant get it to lean out at all on the high end. To be continued….
so here is my 2094 for fun

 

[jasent]

Looks like tinman likes the tea pot muffler. He said it was an iron horse design. I don’t remember seeing iron horse showing a pipe like this but I could be wrong

 

[Nutball]

Yes, ironhorse came out with that like a year ago, but I'm not sure if he came up with it. Someone may have showed it too him, which was then probably made popular from use on his channel.

Dyno testing would be interesting.

 

[jasent]

I’m planning to send my 2094 to joe this spring. Maybe I should include the modified stock exhaust as well to compare.

 

[jasent]

New bear claw inspired pipe I’m playing with.

 

[Fabz]

 

[Hayduke]

Can you fabricate a velocity stack for a 362C?

 

[Fabz]

Why yes … yes I can - the 362c featured in this absolute shellacking of a stock 562xp is the same one that Mastermind (of ope forum fame) himself wanted to purchase from me - I guess it is his favorite model ? … I respectfully declined the offer ….

 

[Hayduke]

What would be the ticket on one of those stacks and when could I get my
Hands on one?!

 

[Fabz]

eBay may have them available, there is another guy , red hair saws or something like that who sells 3D printed versions iirc. The price of 6061 aluminum round stock has gotten so expensive that it’s just not worth my time to machine one-offs and keep the price to under $30/unit shipped! I just incorporate them into builds now as it’s a viable performance enhancer