A MS440 ported from the factory???

[Beer Gut]

No, the 440 and 460 do not have limited coils, never did. I don't follow your question about squish.

If you lower the cylinder .010 to .015 does this change the timing? And is there an adjustment that needs to be made?

 

[066 stihl]

You live in Tn want to come by with your degree wheel and check my timber saws?:msp_scared:


066 stihl

 

[blsnelling]

those numbers sound a little unrealistic in a work saw to me.

Those are real close to the numbers in my 066BB, and it's my go to stumping saw. It's 100% work saw.

 

[blsnelling]

If you lower the cylinder .010 to .015 does this change the timing? And is there an adjustment that needs to be made?

You don't need to work about a thing with that little of a change. You're only talk about about 1-1.5 degrees. You're gaining a couple degrees of intake duration, loosing a couple degrees of exhaust, blowdown staying the same.

 

[blsnelling]

Maybe that's why those 031's he did turn 19,000rpm.:hmm3grin2orange:

Seriously doubt that was advertised as a work saw:msp_scared:

 

[tlandrum]

brad would that bb be the same one that was at my gtg

 

[Beer Gut]

You don't need to work about a thing with that little of a change. You're only talk about about 1-1.5 degrees.

Learning here. But if the change would be more then that the piston still has the same travel and the cylinder ports would be opening and closing faster measured against the crank and eventually would cause a timing issue right? And how would you compensate by cutting the cylinder ports or changing the ignition timing? Bare with me if I don't make sense trying to learn things beyond the scope of where I've gone before.

 

[blsnelling]

brad would that bb be the same one that was at my gtg

Yes.

 

[066 stihl]

On a work saw you want the rpm's at 14,000 to 15,500 with alot of fuel.


The 031 was not a work saw, it was a racing saw. Yes, it would turn 19,000 or so. But, it had booster port cut in it. Had a homemade head on it, a cut down flywheel on it. 066 carb and intake boot. Build to run seconds.

066 stihl

 

[blsnelling]

Learning here. But if the change would be more then that the piston still has the same travel and the cylinder ports would be opening and closing faster measured against the crank and eventually would cause a timing issue right? And how would you compensate by cutting the cylinder ports or changing the ignition timing? Bare with me if I don't make sense trying to learn things beyond the scope of where I've gone before.

This has nothing to do with ignition timing. TDC is always TDC. Tightening squish does not require port work. A change of .010" is only about 1 degree. It's just not a big deal.

 

[tlandrum]

rick ive learned that numbers in your saw or anybody elses saw may not work in the same saw of mine or someone elses. i know the numbers i use are off from what others use but they work for me as your numbers seem to work for you.

 

[parrisw]

Seriously doubt that was advertised as a work saw:msp_scared:

On a work saw you want the rpm's at 14,000 to 15,500 with alot of fuel.


The 031 was not a work saw, it was a racing saw. Yes, it would turn 19,000 or so. But, it had booster port cut in it. Had a homemade head on it, a cut down flywheel on it. 066 carb and intake boot. Build to run seconds.

066 stihl

I know, was just having a little fun. Carry on.

 

[parrisw]

On a work saw you want the rpm's at 14,000 to 15,500 with alot of fuel.

Do you log in close proximity to fuel?

Out here on the West Coast, Timber Cutters must carry everything in and out most of the time, or get dropped off on the side of a mountain via Helicopter, and that means having a somewhat fuel efficient saw, now I've build a few saws that were very thirsty and would not want to pack in on my back that amount of fuel it would take to feed that saw for a day of cutting.

 

[blsnelling]

This building a saw for fuel efficiency has always confused me. It seems to me that if a saw requires a certain amount of fuel to be tuned correctly, then the same saw requiring less fuel is making less power. So isn't it just a matter of making a less powerful saw?

 

[tlandrum]

it takes fuel to make power in my nsvho

 

[blsnelling]

This topic has come up before, Simons thread IIRC. I just never bothered to ask until now. What am I missing?

 

[066 stihl]

Well , the 2171 with a 54mm piston will cut and top 4 good trees. A stock 2171 will cut and top6 tree's.

A good running saw, makes the job more fun. If you run one a day you want go back to stock.

066 stihl

 

[tlandrum]

my 372xpw averages 10 tress dropped and topped all the way out to 4'' and the trees average 24'' on the butt. theres a lot of folks that have run my xpw and know its a quick mean and nasty felling saw.

 

[066 stihl]

Try one with the 2083 piston?

066 stihl

 

[Metals406]

On the coils you want to test non-limited coil. Some are better.......................


On the 066 set, the squish at .020 first. Cut the timing key .020. Then port the ex. at 170-176
trasfers at 130, intake at 170 - 180. On the intake if you go over 184 they don't want to start good and don't like to idle. But, they like to run at 184. After porting the ex. port, measure the inside ex. port, made all the holes in the muffler, be 25% bigger than the ex. port after porting. ( inside ex. port)

If you can get one, use a 056 super piston in it. The top of the piston needs, to be cut some. You will have over 200 psi with that piston. Run a short header pipe, in the muffler on it, maybe 2'' are so.

066 stihl

Is this with blended lower transfers, meaning, blending to the case? Also, how thick are the keys on a 66 (I've never measured), is 20 thou about 1/2 a key?