Mastermind Meets The MS661 Again

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Keith, as I have previously stated, the objective is to have a uniform mix of air/fuel throughout the entire combustion chamber (no lean or rich areas). This simple concept was the key to the dramatic improvements in the performance of GM's traditional style engines. W/O turbulence, your mix will not be uniform.
 
Keith, as I have previously stated, the objective is to have a uniform mix of air/fuel throughout the entire combustion chamber (no lean or rich areas). This simple concept was the key to the dramatic improvements in the performance of GM's traditional style engines. W/O turbulence, your mix will not be uniform.
You are comparing apples to oranges, the 2 stroke needs to push the spent charge out with the fresh charge, mixing is not desirable, and there aren't any valves or extra strokes to achieve, what is done in the car engines.
 
Well fellers GM dont make chainsaws!! Lol! I was interested in mamimum efficiency of the shape of the entrance to the exit of the transfers. Take more material out or leave more in, squared corners vs tapered exits on the upper transfers, flat ceiling vs progressive ceilings on the upper transfers?
 
Well fellers GM dont make chainsaws!! Lol! I was interested in mamimum efficiency of the shape of the entrance to the exit of the transfers. Take more material out or leave more in, squared corners vs tapered exits on the upper transfers, flat ceiling vs progressive ceilings on the upper transfers?
That is where the incredibly simple two stroke gets incredibly complex.
 
So blend the bottom lip at the lower , smooth out any edges/imperfections in the passage, but the upper shape floor and ceiling and both side corners are where I know u have a nice recipe u like Randy?
 
It would include bridges and fingers. You might have noticed that I try just bridges, or just fingers, and sometimes both. I'm still learning you know....

Also think about the size of those bridges and fingers. They likely (I have no way to be certain) flow at a high velocity because they are small......right?

That's why I think (again, I have no way to be certain) they will be better in a work saw than enlarging the existing transfer passages.

All this is just ideas......thoughts.....some observations. What do you think?
 
I just barely knock the lip off the bottom in two port Stihls. I like to think that it keeps fuel from pooling there. It has nothing to do with flow.

Notice that the crank bells are as high or higher than that lip?
 
It would include bridges and fingers. You might have noticed that I try just bridges, or just fingers, and sometimes both. I'm still learning you know....

Also think about the size of those bridges and fingers. They likely (I have no way to be certain) flow at a high velocity because they are small......right?

That's why I think (again, I have no way to be certain) they will be better in a work saw than enlarging the existing transfer passages.

All this is just ideas......thoughts.....some observations. What do you think?
I agree. Just like a waterhose with a broad or smaller exit tip creating more velocity and turbulance!! I never thought about it and guess thats why I called you in!!! Lol
 
These threads get good when we can kick ideas around.

I sure ain't got all the answers though.

Lynn, I'm thinking you may have a lot of good things to input here.
Randy you have a slew of saws out there and 3 certified dyno saws that I know of that exceeded any expectations! Fire away if you are willing . Im all ears
 

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