naturelover
Tree Freak
+1
opcorn:
opcorn:
A MS440 ported from the factory???
- Thread starter blsnelling
- Start date
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Since I'm currently in the middle of rebuilding a Stihl 066, do you have any tips for porting it? Or muffler or carb tips?
Thanks in advance.
Last edited:
woodgrenade
ArboristSite Guru
Making hp as far as limited vs non-limited is concerned?
WadePatton
ArboristSite Guru
no. I'm not Ricky, but I'm pretty sure he's talking about differences in _same model_ coils. if you can get a few to try, you should find some better than others. they're not built "precise" and the differences add up. I'm sure Ricky found the differences with a stopwatch and a tach.
066 stihl
ArboristSite Operative
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
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
komatsuvarna
Arboristsite MVP
That's real close to the numbers in my 066BB. It's by far the strongest 066 I've done. I've got a super nice 064 with an early non-decomp 066 jug that needs some work. I'll keep these numbers in mind. Again, I appreciate the tips.
komatsuvarna
Arboristsite MVP
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parrisw
Tree Freak
Wow, those are high numbers. But if it works, it works!
066 stihl
ArboristSite Operative
On a stock 066 the ex. at around 160 and the intake at 158-160. The higher ex. port timing the lower the compression That's the key, don't kill the compression. On the intake 180 to 184 all you can do.
066 stihl
066 stihl
Beer Gut
A Fine Pilsner
Reading through the thread I found some ?'s when you lower the squish to .025 to .030 from the .045 range would that require a change in timing? Different coil or flywheel key? These's are non ported saws.
Do 044's and 460's have limited coils? If so would there be benefit to trying different ones on a non ported saw. What a bout a 660 limited or not?
This is my setup
044 squish is .025 dual port muff 15 years old
460 squish is .030 dual port muff age unknown
660 dual port 1 year old
Do 044's and 460's have limited coils? If so would there be benefit to trying different ones on a non ported saw. What a bout a 660 limited or not?
This is my setup
044 squish is .025 dual port muff 15 years old
460 squish is .030 dual port muff age unknown
660 dual port 1 year old
066 stihl
ArboristSite Operative
If you run a high ex. port timing you get more rpm's. But, you kill the compression. You need to run a dome piston to help on the compression. The 056 super piston at 184 on the ex. and you will have over 200 psi. It will run............... I have builded one the way.
066 stihl
066 stihl
parrisw
Tree Freak
Any video's of your saws floating around?
066 stihl
ArboristSite Operative
On cutting the bottom of the jug. Yes, you do chance the port timing on the motor. If you cut .025 off. You lower the ex. and transfers .025, you hurt it if you don't raise it back up. By lowing the intake you help it by .025.
066 stihl
066 stihl
No, the 440 and 460 do not have limited coils, never did. I don't follow your question about squish.
parrisw
Tree Freak
Maybe that's why those 031's he did turn 19,000rpm.:hmm3grin2orange:
