Another chainsaw dyno...

[MustangMike]

Since they are heavily debated, I would like to know what you think about bridge ports, and maybe a before and after dyno, as the proof is always in the pudding!

My strongest running (MOFO) MS460 has a D jug with bridge ports, and inexplicably likes the MS461 carb above all others (it is my only saw that does).

I can't explain it, I just experiment and go with what works, but that MS461 carb made a strong saw even stronger. (Based on my timed cuts in Hickory).

Conversely, my CFB Hybrid (also a D jug) would only tune right with a .070 jet MS460 carb, and much prefers that carb.

Both saws run very well but prefer different carbs.

 

[DEastin]

I had a random thought while I was sharpening chains and cleaning saws today... Has anyone ran and/or dyno-ed a ported saw that has a stock muffler? I was wondering if there was any performance gain while still being the same volume as stock.

 

[RI Chevy]

A muffler mod on a stock saw shows gains. So its possible that an unmodded muffler on a ported saw may show a slight loss in performance.

 

[Nutball]

I think it would gain in most cases, but not much. I could be wrong

 

[MustangMike]

IMO, it would be like putting a cam in a car, but not headers. It may help, but you would not see the full benefit.

I'm sure it would also depend somewhat on how restricted the original muffler is.

 

[huskihl]

I bet it’s worth 10-15% on a ported saw

 

[RI Chevy]

What about the stock muffler on the ported saw Kevin?

 

[Duce]

Bet he says loss. Why keep that added heat.

 

[huskihl]

What about the stock muffler on the ported saw Kevin?

That’s what I meant.

 

[huskihl]

I believe Joe tested a 390 with the stock muffler and then with an extra port on the right hand side and gained almost 1 horsepower. Don’t remember if it was ported or not

 

[andyshine77]

I believe Joe tested a 390 with the stock muffler and then with an extra port on the right hand side and gained almost 1 horsepower. Don’t remember if it was ported or not

Amazing! But also not too surprising.

 

[Red97]

I believe Joe tested a 390 with the stock muffler and then with an extra port on the right hand side and gained almost 1 horsepower. Don’t remember if it was ported or not

Ported 390

 

[MustangMike]

Husky I presume?

 

[Red97]

Husky I presume?

Yes

 

[Red97]

Only 1 left....

 

[MustangMike]

Why do they look different? Different filter options?

 

[cuinrearview]

Hey does anybody know where I put my left sock?

 

[Red97]

Why do they look different? Different filter options?

Yes tight top vs low top filter setups.

 

[Dolkitafreak]

Hey does anybody know where I put my left sock?

Is that the crunchy one or the other one?

 

[Dolkitafreak]

Not sure if it’s been mentioned, but I want to see how compression affects power. Would be easiest to test with a two piece head, test say 150, 180, and 220 psi heads all with the same ports. Just something I wanna see!