Author Topic: Did I go a little too far with my 260 exhaust mod?  (Read 517 times)

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Offline Gregsl

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Did I go a little too far with my 260 exhaust mod?
« on: November 04, 2013, 08:30:11 am »
Hi,

I might have rushed things a bit (I try to get all my workshop stuff done when the fiancee is at yoga...)  I think I might have opened up the exhaust a little too much.  I havent been able to try the spaghetti method to check the percentage.  Also, I've heard that you shouldnt open it up more than 80% of your original exhaust port.  Does this mean 80% of the exhaust port size in the cylinder... or the exhaust port at the outside of the cylinder..

I've attached a couple pics to show what I did.  Any thoughts?

I dont mind buying a new muffler if i have to.  I'll take more time to do it next time...

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Offline 660magnum

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #1 on: November 04, 2013, 08:43:21 am »
My chainsaw mufflers are slightly larger than the cylinder outlet of the exhaust.

The outlets of the mufflers are larger than stock. The cookie cutter race saws have outlets as big in area as the exhaust outlet of the cylinder.
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Offline Gregsl

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #2 on: November 05, 2013, 08:42:46 am »
sorry, my quote button isnt working for some reason : 

"My chainsaw mufflers are slightly larger than the cylinder outlet of the exhaust.

The outlets of the mufflers are larger than stock. The cookie cutter race saws have outlets as big in area as the exhaust outlet of the cylinder."

Do you mean the cylinder outlet that the exhaust gasket attaches to? (the one i refer to as outside cylinder in my diagram).  Reason i am asking is there is quite a bit of difference in the opening inside the cylinder versus outside at the exhaust flange side...

Offline 660magnum

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #3 on: November 05, 2013, 10:36:47 am »
Yes, The outside of the cylinder on my ported saws are significantly larger than the inside of the cylinder.

The muffler outlet is as large as the outside of the exhaust port on the cylinder. These chainsaws are much louder than a stock chainsaw.
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
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Offline H 2 H

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #4 on: November 05, 2013, 12:10:28 pm »
026 MM

"People ask me where all my money went, I tell them half of it I spent on gambling, fast women and liquor, the other half I wasted!" W.C.

"..... nothing more funnier than watching some ole coot make a fool out of himself, especially sideways”

"You can't argue with someone that doesn't have any real life experience on the subject."

Offline Gregsl

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #5 on: November 05, 2013, 03:45:27 pm »
wow, how loud is that saw?

Offline HolmenTree

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #6 on: November 05, 2013, 04:49:53 pm »
Greg, every saw is different , my 066 Mag Stihl with it's dual outlet muffler comes with a full baffle inside the muffler over the exhaust port . It puts out all the power I need for what the saw is running at stock.
When I played with tuned exhaust pipes on my race saws years ago when most members here weren't born yet, I experimented with the "exhaust outlet " stinger on the pipe by cutting off lengths of the stinger until the the timed cuts in the log cant dropped in Elapsed Time, that point in length was where I got the best h.p. Same example goes for outlet diameter, the stop watch never lies. ;)
Making a living with a saw since age 16.

Offline H 2 H

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #7 on: November 05, 2013, 05:23:12 pm »
wow, how loud is that saw?

Just a little louder than my other my other 026

IMO feel it runs better also

You have to remember the screen cuts the sound also
"People ask me where all my money went, I tell them half of it I spent on gambling, fast women and liquor, the other half I wasted!" W.C.

"..... nothing more funnier than watching some ole coot make a fool out of himself, especially sideways”

"You can't argue with someone that doesn't have any real life experience on the subject."

Offline Gregsl

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #8 on: November 05, 2013, 05:25:08 pm »
Cool, so I guess I don't have to worry about my modified opening being too big then.

I might still buy another replacement muffler and do a better job of the mod

Offline HolmenTree

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Re: Did I go a little too far with my 260 exhaust mod?
« Reply #9 on: November 05, 2013, 05:26:53 pm »
Cool, so I guess I don't have to worry about my modified opening being too big then.

I might still buy another replacement muffler and do a better job of the mod
If you have a torch to braze silver solder or a mig welder anything can be repaired :D
Making a living with a saw since age 16.

 

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