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Careful.....knowing this place, the next thing is we will be seeing posts where they knock out a few fins and expect a performance increase in their Ranger to run like that Stihl! And its all your fault..that it didn't..and they want new cylinders.

Right after that there will be a discussion if the less weight of removing a few inches of cooling area with a hammer is worth it....

And then some one will try to explain the change in adiabatic conditions in the exhaust port by the moving of the temperature profiles down the cylinder as a result of the change in fin area actually creates an efficiency increase in those many work cycles done every time that piston goes from tdc to bdc...

And then...

Tom will set us all straight.
 
Is there any White Oak there at that property, I need some new trailer planks! I can't find a white oak around here to cut out of.

There was one real nice one, arrow straight and about 24-26 inches DBH.

It's in my firewood pile now!:cry:

Wish I had known you needed it.


Mike
 
I wonder if maybe the missing chip deflector is actually helping the shavings from backing up under the cover when noodling.

It would be an interesting comparison to noodle at the same angle both with and without the deflector.
 
runs like a banshee suckin on alcohol with nitrous injection and supercharger on steroids.

Brad that is a fast saw.
 
Here are a few specs on the saw for you number collectors.

Stock
Exhaust - 97°
Transfers - 122°
Intake - 80°
Blowdown - 25°
Squish - .021"

I had no issues with the stock port timing, plus it's a worksaw. So I didn't go in to change port timing. I did end up lowering the intake to 82°, just cleaning up a little lip on the bottom of the port. A factory gasket was used and the squish unchanged at .021. Ports were widened to within about .050" of the skirt edges, and the transfers widened to within about .050" of the ring ends. The lower transfer ducts were tapered toward the base. The muffler mod only consists of removing the end of the cage and enlarging the factory opening as much as the deflector would cover.
We number collectors thank you, Brad. :laugh:

Let's see if I understand your shorthand correctly, cuz I'm still new at this, and it hasn't completely sunk into my brain yet ?

Exhaust opens at 97 degrees ATDC, so 166 degrees duration ?

Intake opens at 82 degrees BBDC, so 164 degrees duration ?

Squish was 0.021" with the standard factory gasket ? So you didn't have to use a thin gasket to get the perfect squish ?

And you were seeing 160 psi, if I remember correctly ?

Where did the max RPM setting end up after porting ?

I'm glad to see the broken-finned jug getting a new life. :)

Thanks again for the info. :cheers:
 
Your duration numbers are correct. Factory gasket. Max RPMs for cookie cutting would be 14,300-14,500, and that's on a hot saw with the RPMs no longer climbing. I wouldn't leave it there for work. I've got it tuned to 13,500-14,000 in the vids.
 
Here are a few specs on the saw for you number collectors.

Stock
Exhaust - 97°
Transfers - 122°
Intake - 80°
Blowdown - 25°
Squish - .021"

I had no issues with the stock port timing, plus it's a worksaw. So I didn't go in to change port timing. I did end up lowering the intake to 82°, just cleaning up a little lip on the bottom of the port. A factory gasket was used and the squish unchanged at .021. Ports were widened to within about .050" of the skirt edges, and the transfers widened to within about .050" of the ring ends. The lower transfer ducts were tapered toward the base. The muffler mod only consists of removing the end of the cage and enlarging the factory opening as much as the deflector would cover.
We number collectors thank you, Brad. :laugh:

Let's see if I understand your shorthand correctly, cuz I'm still new at this, and it hasn't completely sunk into my brain yet ?

Exhaust opens at 97 degrees ATDC, so 166 degrees duration ?

Intake operates at 82 degrees before or after TDC, so 164 degrees duration ?

Squish was 0.021" with the standard factory gasket ? So you didn't have to use a thin gasket to get the perfect squish ?

Both intake and exhaust were widened to within 0.050" of the skirt ? Doesn't that increase the intake width by a larger % than the exhaust ? Just wondering if I should 1) make the intake as large as the skirt allows, as you did, or 2) widen the intake only the same % as the exhaust ?

And you were seeing 160 psi, if I remember correctly ? (that would be a mere 136 psi at my altitude, ugh ! ! !)

Where did the max RPM setting end up after porting ?

Good on you and your customer for giving the broken finned jug a fair chance. :)

Thanks again for the info. :cheers:
 
What oil did you use on that mix Brad?
Klotz R50 @ 32:1. 40:1 would be fine. 50:1 probably would be too, but I recommend 40:1 just for insurance on a ported saw.

Both intake and exhaust were widened to within 0.050" of the skirt ? Doesn't that increase the intake width by a larger % than the exhaust ? Just wondering if I should 1) make the intake as large as the skirt allows, as you did, or 2) widen the intake only the same % as the exhaust ?

There was not much room to widen the exhaust. There was quite a bit more room on the intake, plus I squared up the floor considerably. I don't go flat, but I do run the intake more square than the exhaust since no rings ride over the floor of the intake. I failed to mention it earlier, but I did lighten and flow the piston as well. I don't remove material soley for the purpose of lightening it, but that's a nice benefit of the flow work.
 
nice vids

Thanks for the videos Brad. The port job looks like it came out well. I'm trying do my homework, I'd love to do a port job on a Stihl 044 project saw I just bought. Perhaps I could put a big bore kit on it and hear it scream. That was a good sized tree as well. Have a great weekend!:clap: :clap:
 
Looks like a nice strong running saw. The video looks great too, nice and crisp. What kind of camera are you shooting it with?
 
Same saw, same cylinder. The new owner didn't want it replaced and wanted it ported. I put about 1 1/2 tanks of fuel through it in 80° weather giving it very little time to cool between cuts. Even with the new piston, I spared it no mercy. If it was going to seize, I wanted to make it happen right now.

Brad don't worry about overheat, two corners missing aint no thing. If I posted a pic of a 371 cylinder I have here, that has been in service for a year in a landscape company, it would put all the nay sayers to rest! This time around its getting ported more and pop up time.
 
Brad don't worry about overheat, two corners missing aint no thing. If I posted a pic of a 371 cylinder I have here, that has been in service for a year in a landscape company, it would put all the nay sayers to rest! This time around its getting ported more and pop up time.

I know, it makes you wonder why they even put them on there. I believe the whole cooling fin thing to be a big myth, kinda like a Hary Potter novel:)
 

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