Before plunking down the money to have someone do a much better job. I was wondering anyone ever just cut the sides of the deflector bend it back drill your holes and bend it back down? Does that allow to much heat to hit your plastic on top? The baffle located through the inlet looked like it had 3 holes leading toward the outlet. Anyone ever just jam a bur on a grinder in there to rip most of that out or make one large hole? Seems easy enough if the deflectors sides can be cut and bent. I do not have a welder currently to close the sides back up
That's basically how I did a 550 and 562 . I used a carbide bur to enlarge the baffle holes ,then enarged the exit after bending the deflector . If you look through the exit,you can see through to the exhaust . It lets the saw breath ,but it's still reasonably quiet .
I gutted the first, took everything out including all the metal under the deflector. Loud as hell and not a huge gain in power. So sold that muffler and got another. 2nd one just drilled a couple more holes in the baffle and a big hole under the deflector, next to the org outlet, did not have to bend the deflector up to do this. Quieter and I swear it seems to be stronger than the first one.
Probably has a little more back pressure than a completely gutted muffler! Some back pressure is needed for good overall performance in my opinion.
Figure someone like mastermind or tlandrum would do a much cleaner and better job than i. So i await now on a new muff in the mail muahahah Support small buisness too!
Back pressure not so much needed in a 2 stoke, but a straight open exhaust isn't so good either. When gutted the exhaust port lines up with the outlet and gives the exhaust a straight shot out. As I understand it's better to have the exhaust bounce around and exit out the side of a muffler. The 562/550 muffs are a different animal than older models.
The only time I want backpressure to make power in an exhaust system is if there's a turbocharger involved.
I guess I meant more of a resistance of flow rather than an actual back pressure. Wouldn't too fast of a flow cause too much heat loss in the combustion chamber and cause incomplete combustion/loss of power, similar to an epa stove? Kind of what I was picturing in my head anyway.
Resistance of flow isn't good either. We want the exhaust out of there asap. But there is the scavenging effect of the muffler to consider. It has something to do with resonance or sound wave bouncing off the inside front of the muffler. I really don't understand it and am probably explaining it wrong. But I did experience it with the two mufflers I did on my 562. And have heard similar results from others and the 550 crowd.
