working on other builders saws

[afleetcommand]

Being a theoretical two stroke novice, looks to me that "tree monkey" has focused on a bunch of those "more isn't always..MORE (Unless it's Lynard Skynard's Free Bird)" type deals all wrapped up in one saw. Effect on the piston life with over sized intake port being one,...maybe less isn't more relative to squish? LOL JUST to be a PITA, anyone ever figure how much percentage squish happens with paper based gaskets over a few heat cycles? And relative to intake port size, shape, and flow characteristics....anyone wonder why those "dimples" are added to many intake pipes? (And why I suspect somewhere out there folks might put a small "step" in the exhaust ports) Always thought timing and the transitions between devices were whats critical vs. just SIZE. Like from port to cylinder, air box to carb. Case to transfers. (Compression too....) SO much stuff to consider and these posts can spark real interesting discussion where all can learn...

 

[Lightning Performance]

Do I know you by another name?

My piped 390XP is the only saw I've ever really attempted to take past a worksaw

I'm too chicken to put alky in my saws, lol.

Nope you don't but I'm a lurker and I've been around for many years.

bummer...

Oh. Why so chicken?

Your style of port work will lend it's self to racing. All those times you know you wanted to go farther in the port area is just what a big intake set up and piped race saw would want. My 2cts

 

[XP_Slinger]

Dimples in the intake create surface turbulence that prevents fuel from falling out of suspension then sticking or puddling on the metal (in case anyone was curious). Made the polishing intake mistake on an old wheeler back in my day. LOL

 

[jacob j.]

LOL JUST to be a PITA, anyone ever figure how much percentage squish happens with paper based gaskets over a few heat cycles?

In the early 90's, Stihl issued several models in Asian, African, and South American markets with a thick paper base gasket, to address the inferior grades of fuel often found in those areas. They subsequently found that a thick paper base gasket has a very high rate of failure.

 

[kingOFgEEEks]

This is the first I've heard that squaring an intake beyond carb bore diameter is a bad thing...very interesting with sound theory. The way my brain is thinking on it, I see a squared intake acting as a plenum in that it somewhat stores some air fuel mix at the piston for the initial gulp upon port opening which "should "increase the volume of the intake charge with slightly lower velocity giving the saw greater power at higher RPM. That whole Velocity vs Volume dance is a delicate balance and as far as I understand it when you gain in one, you lose in the other to a degree.

I would imagine a saw with a narrow, high velocity intake tract would have a much broader power band at lower rpm.

Thinking out loud here guys

Q=Av or Volume = Area x Velocity. If you increase the area, you decrease the velocity.

Think about a garden hose (5/8" diameter). If you plumb your house to have an outside garden spigot, and you plumb the line with 1/2" pipe inside the house, you will never get full flow at the garden hose, and you end up disappointed. If you plumb the house with 3/4" pipe the whole way, you will have excess capacity that the garden hose can't handle. You'll never flow more than the weakest link in your system, so no point going bigger.

Not an expert, just thinking it through.

 

[XP_Slinger]

Q=Av or Volume = Area x Velocity. If you increase the area, you decrease the velocity.

Think about a garden hose (5/8" diameter). If you plumb your house to have an outside garden spigot, and you plumb the line with 1/2" pipe inside the house, you will never get full flow at the garden hose, and you end up disappointed. If you plumb the house with 3/4" pipe the whole way, you will have excess capacity that the garden hose can't handle. You'll never flow more than the weakest link in your system, so no point going bigger.

Not an expert, just thinking it through.

Excellent info...Thank you

 

[Moparmyway]

Q=Av or Volume = Area x Velocity. If you increase the area, you decrease the velocity.

Think about a garden hose (5/8" diameter). If you plumb your house to have an outside garden spigot, and you plumb the line with 1/2" pipe inside the house, you will never get full flow at the garden hose, and you end up disappointed. If you plumb the house with 3/4" pipe the whole way, you will have excess capacity that the garden hose can't handle. You'll never flow more than the weakest link in your system, so no point going bigger.

Not an expert, just thinking it through.

Except the fuel is evaporating
Liquids cant be compressed, but gasses can

 

[thomas1]

Q=Av or Volume = Area x Velocity. If you increase the area, you decrease the velocity.

Think about a garden hose (5/8" diameter). If you plumb your house to have an outside garden spigot, and you plumb the line with 1/2" pipe inside the house, you will never get full flow at the garden hose, and you end up disappointed. If you plumb the house with 3/4" pipe the whole way, you will have excess capacity that the garden hose can't handle. You'll never flow more than the weakest link in your system, so no point going bigger.

Not an expert, just thinking it through.

What's the weakest link in the chainsaw system?

 

[Majorpayne]

What's the weakest link in the chainsaw system?

Between the ears?

 

[T.Roller]

What's the weakest link in the chainsaw system?

I would say the carb or boot. Seems to be the restrictive point.

 

[T.Roller]

I'm new to this but I would think the stroke would also have alot to do with it too

 

[DSS]

What's the weakest link in the chainsaw system?

Operator

 

[Mastermind]

What's the weakest link in the chainsaw system?

The chain. If people would learn to properly sharpen and maintain their chain........porting would just be a silly fad.

 

[T.Roller]

The chain. If people would learn to properly sharpen and maintain their chain........porting would just be a silly fad.

I misunderstood the question. I thought he was asking about the weakest link in the fuel system of a saw

 

[Basher]

The chain. If people would learn to properly sharpen and maintain their chain........porting would just be a silly fad.

But, but, what if both engine and chain are perfect for that piece of wood at that time ,day, pressure, altitude ,temp and humidity ?

 

[Mastermind]

But, but, what if both engine and chain are perfect for that piece of wood at that time ,day, pressure, altitude ,temp and humidity ?

That my friend is a magic moment.

 

[paragonbuilder]

What's the weakest link in the chainsaw system?

In my opinion, there are 2 things needed to really create more power, tunable exhaust pipe, and better cooling.
Neither of which is feasible on a work saw, these engines are very weak for their size compared to engines with those 2 features.


Sent from my iPhone using Tapatalk

 

[thomas1]

The chain. If people would learn to properly sharpen and maintain their chain........porting would just be a silly fad.

I think your business is safe.

 

[Mastermind]

I think your business is safe.

Yeah I do too.

August is almost full.

 

[Basher]

That my friend is a magic moment.

Doesn`t happen often,but when it does you will remember it.