woods port saw video thread

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My God, would you give it a fricken rest already???!! We all get the point, you don't like Jason. Quit acting like a child and move along... your constant ******** on this thread when it gets back to the very interesting actual topic has more than gotten old! If you have an actual problem with Jason, settle it between you and him! If you don't actually have an issue to work out with him, **** and butt out!
 
jmssaws said:
What's your thoughts on case capacity and how it affects everything else?
Does pressure trump volume?
Less overall charge under a little more pressure make more power than more charge moving slower or do they cancel each other out?
What If you ran less intake to gain crank compression and got both?
I think about it a lot and haven't made up my mind.
Click to expand...
My theory?

No saw is the same. All the parameters change based on what you do to any one thing.

If I wanna build a cant saw to turn 14k in that soft little square piece of wood with a wicked chain, big-ish ports. Big enough to flow but small enough to keep some velocity when the piss revving saw finds the instant load of hitting the cant.

Worksaw? The smallest roundest ports I can get by with. Piston wear and low end grunt.

Velocity and flow are interrelated. If the tunnels and ports are too big, they will flow great. The minute you push on the saw, the saw will lose torque and die. Charge inertia needs to be maintained.

Case volume? Why do hybrids want to rev? Any given swept volume needs to be fed and will pump a maximum amount of air. How do you flow the same amount of air with a smaller gulp? Turn the engine more. Try to overfill the case? More spitback and same pressure. There's also some charge inertia effect on the intake port. A smaller port will keep inertia and velocity enabling you to run more intake duration without losing torque.

I try to get inside the head of the German engineers that designed the saw. They weren't dummies.

I used to hog ports out. Now I grind a lot less but in the place I think is correct.

I'm not a pro. Don't claim to be and don't want to be. It takes me so long to do a single saw that I'd be out of business in a week.

My opinion and theory is worth what you just paid for it, zero.

In so far as blowdown, I think what you are trying to say is that physically lower exhaust roofs can tolerate less blowdown because there is less combustion pressure to overcome as the piston moves downwards.
 
drf255 said:
My theory?

No saw is the same. All the parameters change based on what you do to any one thing.

If I wanna build a cant saw to turn 14k in that soft little square piece of wood with a wicked chain, big-ish ports. Big enough to flow but small enough to keep some velocity when the piss revving saw finds the instant load of hitting the cant.

Worksaw? The smallest roundest ports I can get by with. Piston wear and low end grunt.

Velocity and flow are interrelated. If the tunnels and ports are too big, they will flow great. The minute you push on the saw, the saw will lose torque and die. Charge inertia needs to be maintained.

Case volume? Why do hybrids want to rev? Any given swept volume needs to be fed and will pump a maximum amount of air. How do you flow the same amount of air with a smaller gulp? Turn the engine more. Try to overfill the case? More spitback and same pressure. There's also some charge inertia effect on the intake port. A smaller port will keep inertia and velocity enabling you to run more intake duration without losing torque.

I try to get inside the head of the German engineers that designed the saw. They weren't dummies.

I used to hog ports out. Now I grind a lot less but in the place I think is correct.

I'm not a pro. Don't claim to be and don't want to be. It takes me so long to do a single saw that I'd be out of business in a week.

My opinion and theory is worth what you just paid for it, zero.

In so far as blowdown, I think what you are trying to say is that physically lower exhaust roofs can tolerate less blowdown because there is less combustion pressure to overcome as the piston moves downwards.
Click to expand...

Did you run that 036 yet that you did machine work only?


Sent from my iPhone using Tapatalk
 
drf255 said:
My theory?

No saw is the same. All the parameters change based on what you do to any one thing.

If I wanna build a cant saw to turn 14k in that soft little square piece of wood with a wicked chain, big-ish ports. Big enough to flow but small enough to keep some velocity when the piss revving saw finds the instant load of hitting the cant.

Worksaw? The smallest roundest ports I can get by with. Piston wear and low end grunt.

Velocity and flow are interrelated. If the tunnels and ports are too big, they will flow great. The minute you push on the saw, the saw will lose torque and die. Charge inertia needs to be maintained.

Case volume? Why do hybrids want to rev? Any given swept volume needs to be fed and will pump a maximum amount of air. How do you flow the same amount of air with a smaller gulp? Turn the engine more. Try to overfill the case? More spitback and same pressure. There's also some charge inertia effect on the intake port. A smaller port will keep inertia and velocity enabling you to run more intake duration without losing torque.

I try to get inside the head of the German engineers that designed the saw. They weren't dummies.

I used to hog ports out. Now I grind a lot less but in the place I think is correct.

I'm not a pro. Don't claim to be and don't want to be. It takes me so long to do a single saw that I'd be out of business in a week.

My opinion and theory is worth what you just paid for it, zero.

In so far as blowdown, I think what you are trying to say is that physically lower exhaust roofs can tolerate less blowdown because there is less combustion pressure to overcome as the piston moves downwards.
Click to expand...
I rarely enlarge a intake,there generally bigger than they need to be stock,I might square up the corners a little and ruff it up.
Transfers i don't widen the lower unless I have to,the only part I make bigger is under the bridge,I widen the exhaust side from the corner to the lowers to make it straight which increases the angle more towards the intake,the intake side of the upper I take far as I can to increase the angle again. That's all,nothing is hogged out but the one corner,opening issue the smallest point.

I widen the exhaust to 65% or what the skirt allows.
I also run as flat of a exhaust roof as I can get away with.
That's all I do.
I spend a lot of time on the way the transfers dump and on the shape of the exhaust.
I'm not a number type guy,if I build my best ever 394 at 99 117 82 I won't do another one exactly the same as it because it's not the numbers making it the best,build 20 more like it with the same numbers and not beat it.

I don't see how more intake duration increases velocity,the case will only hold so much and the rest is spit out,I want to get it closed and start building case compression to feed the bigger transfers.

I spent almost 2 years now working on the way I do most saws now just so they would be different,be pretty boring if we all done the same thing.
 
blsnelling said:
No porting yet on this one. It has a pop-up piston, timing advance, and a muffler mod. It already runs fantastic!

Click to expand...

The right Stihl MS440 cylinder with a .010 band cut (just to clean it up) and a base cut to correct squish+muff mod+timing advance can run right on the tails of a fully "ported" one without touching a port.

Sometimes we can make them worse than the factory, many times.
 
jmssaws said:
I rarely enlarge a intake,there generally bigger than they need to be stock,I might square up the corners a little and ruff it up.
Transfers i don't widen the lower unless I have to,the only part I make bigger is under the bridge,I widen the exhaust side from the corner to the lowers to make it straight which increases the angle more towards the intake,the intake side of the upper I take far as I can to increase the angle again. That's all,nothing is hogged out but the one corner,opening issue the smallest point.

I widen the exhaust to 65% or what the skirt allows.
I also run as flat of a exhaust roof as I can get away with.
That's all I do.
I spend a lot of time on the way the transfers dump and on the shape of the exhaust.
I'm not a number type guy,if I build my best ever 394 at 99 117 82 I won't do another one exactly the same as it because it's not the numbers making it the best,build 20 more like it with the same numbers and not beat it.

I don't see how more intake duration increases velocity,the case will only hold so much and the rest is spit out,I want to get it closed and start building case compression to feed the bigger transfers.

I spent almost 2 years now working on the way I do most saws now just so they would be different,be pretty boring if we all done the same thing.
Click to expand...

Do you think making the intake floor flatter would suck the charge in quicker? And possibly could run less intake.
 
X 66 Stang347 X said:
Do you think making the intake floor flatter would suck the charge in quicker? And possibly could run less intake.
Click to expand...
I think a flat intake floor makes it use gas and wear out the intake skirt.

I don't think about the intake opening
I think about when it closes.

In my mind there isn't velocity or whatever you want to call it until the intake closes and and builds cranking compression and then dumps into the cylinder so in my mind how it gets to the crank case isn't nearly as important as what happens when the intake closes.

That's my thinking
 

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