Muffler mod thread

[Ronie]

I normally just do simple basic ones, gut it if I can or drill out the baffle and a bigger outlet.

361

 

[Ronie]

660

 

[Ronie]

550 562 620P

 

[Wonka13]

Nice work!! I usually buy whatever random muffler is cheapest for a “donor”, and scavenge the deflector off the thing to mod the muffler I’ll be using….$12 usually…not as pretty as yours, but they work

 

[Ronie]

Nice work!! I usually buy whatever random muffler is cheapest for a “donor”, and scavenge the deflector off the thing to mod the muffler I’ll be using….$12 usually…not as pretty as yours, but they work

That looks good!

 

[Wonka13]

That looks good!

Thanks! Sheetmetal work done with a 28oz framing hammer & a 2x4 for an anvil!! No joke!. Not sure why my pictures always post sideways

 

[tacotodd]

@Wonka13 , it just doesn’t matter what tool(s) you used. The end results speak for them selves, and in a VERY good way I’d say

 

[jasent]

My go 2 deflector design. Costs me about $3 to make

 

[Red97]

I have deflectors if anyone is looking. Have 2 other sizes than whats pictured. And all of them can be made stainless tooml.

 

[Wonka13]

I have deflectors if anyone is looking. Have 2 other sizes than whats pictured. And all of them can be made stainless tooml.
View attachment 334

I’m diggin’ those, shapable with tin snips?

 

[Red97]

I’m diggin’ those, shapable with tin snips?

Yes 20g the mild steel snip great.

The stainless take some effort and a good pair of cutters but still doable by hand.

 

[Wonka13]

Good deal, thank you!

 

[854tga+]

I had Walkers Saw Shop ship me this muffler for our 390XP

 

[jasent]

What paint do you guys use on your exhaust. I tried a high temp engine paint but it cooked off in a few minutes of running. Stanky!

 

[Ronie]

What paint do you guys use on your exhaust. I tried a high temp engine paint but it cooked off in a few minutes of running. Stanky!

I use VHT header paint

 

[BUDDY G]

just finished up my little 372

 

[Wonka13]

just finished up my little 372

That’s one serious MM!! Any concerns with the lack of backpressure with it being so open?

 

[Fabz]

I don’t think a guy can go wrong with a tube exhaust saw. Some fiddling around with diameter ,length, single, double or even triple tubes can make a saw pull with a nice throaty tone and seem to go easy on the mix. Maybe not the most peak dyno HP of a gutted muffler dual port side/side but the most usable torque. I get some guys are cuttin where spark arrestors are a necessity and Run with the deflectors. The side/side make HP though with the downside of seeming to use the most fuel. Did I mention they are also extremely loud ? Back pressure isn’t a concern wide-open in the cut though, and imho you want virtually none or even negative pressure to create “pull” at resonance

 

[tacotodd]

Well, my mod was lots more simple. I took my 372xt jungle muff and enlarged the outlet to approximately 13/16”. Wow, did THAT THING CAME ALIVE! I couldn’t believe what that simple mod did. Like going to a 90ishcc saw. I wa impressed with my simple little modification. Easy-pezy.

 

[jasent]

Personally I have not seen any gains with muffler exit over 75% port size Have seen zero back pressure lean a saw out to dangerous level and then when fattened up spit fuel out exhaust while still trying to run lean. Jme with that