066 Stihl"Nowhere to go" for woods saw modification?

[Crofter]

I have run a stock 066 a bit and wonder if there is much to be gained in modifying it for a woods saw (beyond muffler). I sure cant see it needing much more compression or timing advance or I'd need to tow it to start it! Are some saws as they come from the manufacturers about as good as it gets? Some saws apparently turn from a toad into a prince when our builders kiss them. How about the 066 Stihl?

Frank

 

[Jacob J.]

Frank- the 066 is a great saw stock. They're reliable, fast, and have plenty of power. They do benefit from a full woods treatment, Dozerdan and Ken Dunn have both had good luck with woods mods on the 066. Ken once posted that the 066 could only gain about another 20%-25 more power from a full woods mod, compare that to the 385 which can gain 50% or so.

 

[rupedoggy]

I agree with Ken and JJ, the 066 is factory helped. The ignition, compression, port timing and muffler are all better than most saws. That is why the 066 has such a loyal following with those that use saws for a living. That is not to say a little help can not be given to them. The 064 was the little brother to the 066 and was also a great saw. I think Dennis Cahoon liked them a lot when he was in the woods and working for a living with saws. Mike

 

[ehp]

no saw that comes from the factory is as good as it gets but the 066 with the right carb and muffler is pretty good
i have maded up 2 066 saws for stock class racing , now these are stock , no porting , air filter in place and no muffler mod. and they are as fast as any 3120 stocker or 084/088 saw that has been geared and chained to there powerband
but yes there is more left in the 066 and that is why it is my favourite saw to cut with in the bush

 

[sawracr]

Just put a bar and chain on a saw ( MS660 ) done by a long time porting specilist here in California, the saw was built for the woods, had a lot more power than stock, could not keep 50ga. chain on it while limbing. Yes there is room for improvement! Jon

 

[Koa Man]

I have a Walkerized 066 and it will easily outcut my stock 084. I don't use the 084 anymore except for the extremely rare ocasions when I need a bar length over 36". I think the 066 is one of the two best saws made by anybody. The other is the 020T, now the MS200T.

 

[timberwolf]

Does the potential 20-25% preformance gain include the 15% that can be easily recognized by adjusting the muffler?

If thats the case, were only talking 5-10% after the muffler. Seams like a lot of $$$ and trouble to get such a small improvment.

Has anyone had experiences with milling or other heavy use with a full woods modification? when i'm using the 066 it spends about as much time cutting along the grain as accross it.

 

[Oregon_Rob]

Contact Kevin. He as used an 066 of a lot of milling. I think you will find it comes highly recomended.

oops, missed that part about the full woods mod. I believe that Ralph Fosters 088 is modified.

 

[Harry]

064 to a MS660 Muffler question

I have an old 064 thats pretty tired... I also have a newer MS660 that I got about 3 months ago. Being that the saws are pretty similar does any one know if the muffler off a 064 will fit on the newer MS660 ? The reason is that the 064 muffler is old enough that its open inside and from the looks of this MS660 they have the new ones choked way down. I haven't looked into it but I thought that I'd ask the question before taking a closer look.

Any info would be appreciated
thanks
Harry

 

[Jacob J.]

Timberwolf- you won't get 20-25% on an 066 just by opening up the muffler. You might get 6-7% if you're lucky.

Harry- The mufflers are not interchangeable. The 064 cylinder was set back further than the 066 cylinder was. You can modify the muffler to fit, but it's a bit of work.

 

[Harry]

Thanks Jacob J. Looks like I'll have to gut the new MS660 muffler then. Thanks, that saved me some time looking into the 064 swap thing I was thinking about.

Harry

 

[Crofter]

Harry:

There are pictures here somewhere on the chainsaw forum with details on what to do on the interior baffle box on the 066, also on resising outlet. Best not to go too extreme to start with as you get to the point of blowing out more fuel for nothing and actually losing power if you open beyond a certain point.

Frank

 

[timberwolf]

From what I observed with some tests made when opening up a 260, the gains easily appered to be in the range of 15%. Looking at the restriction on the 066 I would think the same gain is potentially there.

stock there is one hole in the muffler about 3/8 in diamiter and one slit about 3/32 by 5/8. The port is more like 3/4 by 1-1/8. It seams the general opinion is that the exaust outlet be at least the size of the port as the charge expands as it moves out through the port and muffler.

Brian

 

[rahtreelimbs]

This might help.

http://www.arboristsite.com/showthread.php?s=&threadid=4456&highlight=muffler+mods

 

[Ryan Willock]

Dennis Grefferd modded my 066, its one mean saw even with the simi-chisel that I use on the landing!

 

[rahtreelimbs]

This straight from Yoda:



The muffler work that we do to the 066 muffler to increase the power is as follows; go inside and cut the end out of the stainless steel perforated box at the exhaust inlet, match the exhaust entry and gasket to the barrel opening, and on the 066 go to your local stihl dealer and buy the ported cover for the 066 magnum muffler. its 31.00 dollars and has a screen and deflector over the port
this will add 15-20 % to the power level. you can also cut a port in your existing cover, if you do make the port 1 1/2 long by 7/16 tall

ken
kdhotsaw@hotmail