My first Stihl 440 mod project

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stihlfarmer said:
I have read all the WHS info and got an Idea for what is possble

How much of this can I do myself?
Good Day to You Stihlfarmer,
Do consider an increase of compression by eliminating the jug to crankcase gasket. I have always noticed a nice increase in torque doing this. Elimination of the gasket will lower the cyl. to the piston aprox. .010-.012 (Reducing the Squish Volume).

I use Permatex Ultra Gray to replace the gasket. A thin film applied to the crank surface & torque the jug down, small excess will squeeze out. Then check the piston to jug clearance at TDC thru the spark plug opening, using .025-.030 soft solder at four points 12-3-6-9 o'clock. Min. clearance .022-.025. (Probably no problem on your 440).
Replace the rings with oem Stihl. (unless near new) well worth the $ while your in there. Hone very lightly if no scratches (400 silicone 2-3 fingers & lite oil.) Just to break the glaze.
Along with muffler mods as the others have suggested you should have a very nice increase in power that you WILL FEEL, a long lived saw & (will be near stock with the gasket replaced) for future port & timing work by an experienced builder. (If you want to spend $250+ or -).
I have done this type of mods to 5-6 saws & a few weed eaters, I have always have been pleased with the results. A few even impressed me..........
 
Spacer

SmithEC said:
There can never be too many pictures on AS.

You already know what the stock muffler looks like because that's what you've got.

This is the dual port from the front.

http://img.villagephotos.com/p/2005-11/1105978/127(Medium).JPG

127(Medium).JPG




This is the dual port from the side. Do you see how neatly I enlarged the hole in the side?

http://img.villagephotos.com/p/2005-11/1105978/087(Medium).JPG

087(Medium).JPG




This after I Dremeled out the baffling.

http://img.villagephotos.com/p/2005-11/1105978/118(Medium).JPG

118(Medium).JPG




Actually, it's a different muffler. It does illustrate the DPM cover though, right? You can buy this muffler in the States, just so you know. P/N 1128 140 0616.
Hi
I noticed in your pictures that there is a spacer between your dawgs.On the bottem of them. I just bought a ms440 and have the big dawgs. Is the spacer suppose to be there or is it something you added?Thanks. Gary
 
does the ms440 come stock with 2 dawgs? i bought a 440 last year new and it only has 1 dawg.
 
stuff_2768.jpg
If you feel comfortable, try opening up your exhaust port a little and polish it out. At first I would only go side to side until you get comfortable. Also practice on a junk cylinder first. If you need a junk cylinder to practice with let me know and I can get you one.
The best way to do this is follows: Take the rings off of your piston and insert it into the cylinder. Align the piston up as it would be on the connecting rod. Now take a sharp pencil and trace the outline of the exhaust port on the skirt. this will show you how much room you have. If you go past the skirt edge you will ruin the cylinder. Try to leave yourself at least an 1/8" on each side to start out with. this is a very good mod for some one who wants to start with. Also, it was mentioned earlier that you could take out the gasket. Yes and it is a good mod but a few things to mention. First is to check the squish clearance. You do not want to go any closer than .020 Some saws you can take the gasket out and some need a thicker gasket. You might find that your saw is some where in between and you need a thin gasket. the point is, to use the squish #'s to determine what to do not just doing it and thinking you got something. You might end up getting it too tight and ruining your saw. Now if you do have the room to take your gasket out and you use a sealer; groove and cross hatch the bottom of the cylinder to prevent leaks. I am also posting picks so that you can see.
stuff_2771.jpg
 
Looks like the 440 has room for a double-barrel arrangement. Here's a picture of my 066, Jwoods dual-port muffler. It also has the equivalent of the jug gasket removed as was suggested above.

Bumpr ran this saw at Woodsjunkies GTG. Ask him how he likes it.

Joe
 
While I can't compare to pre-mod, I can sum my experience with a "BOIIIIIINNNNGGGG!!"

It was cool. Compare my time with the 066 (5.94 sec) versus my time with my DP/green MS460 (6.06 sec). Speaks for itself.

Jwoods' times were better with 066 versus 460, too as one would imagine.

http://www.hotsaws.com/showthread.php?t=170&page=6
 
Just look at the smile on this guy's face!

Stihlfarmer- whatever you do to your saw, have fun!
DSC00823.jpg
 
Last edited:
bump_r said:
While I can't compare to pre-mod, I can sum my experience with a "BOIIIIIINNNNGGGG!!"

It was cool. Compare my time with the 066 (5.94 sec) versus my time with my DP/green MS460 (6.06 sec). Speaks for itself.

Jwoods' times were better with 066 versus 460, too as one would imagine.

http://www.hotsaws.com/showthread.php?t=170&page=6


nice.. but the wood is kind of small for an 066... All it really shows is that the chain speed was similar with the two saw. Bury them in say 24x24 (or bigger) wood... and then time them
 
ironhead said:
Hi
I noticed in your pictures that there is a spacer between your dawgs.On the bottem of them. I just bought a ms440 and have the big dawgs. Is the spacer suppose to be there or is it something you added?Thanks. Gary

The spacer is actually described as a chain catcher. P/N 1122 650 7700. Paid $5.94 at a dealer that I suspect charges right at MSRP. The P/N includes 4 separate pieces. It's actually attached to just the outer dawg in such a way that the sprocket cover still comes off just as if that piece weren't there.

The saw in the picture is a 460. It's possible that the same part for the 440 may be assigned a different P/N. I know that the same part for a 361 has a different P/N, so it's not universal. I don't have an IPL for a 440 so I can't say.

Maybe someone here knows the answer.
 
Dawgs

Vman said:
does the ms440 come stock with 2 dawgs? i bought a 440 last year new and it only has 1 dawg.
They come with 1 dawg but i can give you the numbers if you want a set of the big dawgs for the 440. They run about $12.50 each. Pm me if you want the #'s.
 

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