Saw video thread

[huskihl]

Squish band is supposed to be narrow from what I've read.

 

[Time's Standing Stihl]

Here's a 064 w/066 topend I just did a little rework to. It'll turn 13K with a lightish load, loves to work at 12K, and can be lugged down to 8K without even thinking of stalling.

What size of a sprocket is it wearing? Looks like some hard wood

 

[jmssaws]

Squish band is supposed to be narrow from what I've read.

That's what I've always heard

 

[Moparmyway]

What I mean is,do you think a larger chamber not squish or a more narrow band affects performance?

Dodge made a huge chamber in the 426 Hemi, but they filled it with the piston.

I'm of the impression that chamber and piston shape, as well as size are directly related to each other. Chamber displacement should be kept as small as possible without going to far on compression. I'd rather fill a chamber with a piston than cut a tiny chamber. Surface area has to play a role in power output during the period that the fuel begins to burn. In my mind, pushing down on 6 square inches of piston with combustion pressure is better than pushing down on 2 square inches of piston with the same pressure.

 

[paragonbuilder]

Dodge made a huge chamber in the 426 Hemi, but they filled it with the piston.

I'm of the impression that chamber and piston shape, as well as size are directly related to each other. Chamber size should be kept as small as possible without going to far on compression. I'd rather fill a chamber with a piston than cut a tiny chamber. Surface area has to play a role in power output during the period that the fuel begins to burn. In my mind, pushing down on 6 square inches of piston with combustion pressure is better than pushing down on 2 square inches of piston with the same pressure.

That makes sense to me Kevin...

 

[jmssaws]

Dodge made a huge chamber in the 426 Hemi, but they filled it with the piston.

I'm of the impression that chamber and piston shape, as well as size are directly related to each other. Chamber displacement should be kept as small as possible without going to far on compression. I'd rather fill a chamber with a piston than cut a tiny chamber. Surface area has to play a role in power output during the period that the fuel begins to burn. In my mind, pushing down on 6 square inches of piston with combustion pressure is better than pushing down on 2 square inches of piston with the same pressure.

That's what I always have been told.

What I did to the 460 is decrease the width of the band which creates surface area on the piston.

Instead of cutting it on a taper like you suggested above I just reduced the width of the band.
I also used a shorter plug in the decomp.
Lost almost 10lb from that.

 

[Red97]

Do you think chamber size affects performance?
Say a 50cc chamber at 200lbs and a 70cc chamber at 200lbs
Think they will run different?
I don't know but I've always heard you want it small as possible.

Thoughts?
Be something that needs to be tested

I feel the bigger the chamber, the more air/fuel you can trap above the piston. The more air/fuel you can trap/burn, the higher potential for power output.

 

[RI Chevy]

Anyone make a Hemi piston and cylinder for chainsaws? Lol

 

[Red97]

Anyone make a Hemi piston and cylinder for chainsaws? Lol

Lots of saws have a hemi chamber, along with a domed piston.

 

[RI Chevy]

Cool. The older ones or new ones?

 

[Moparmyway]

Anyone make a Hemi piston and cylinder for chainsaws? Lol

Close, but not quite

 

[RI Chevy]

Cool. [emoji106] Thanks for the pics.

 

[94BULLITT]

The saw would have to be a 4 cycle to be a hemi.

Now I wonder if the 4 mix is a hemi.

Sent from my SPH-L710 using Tapatalk

 

[Red97]

The saw would have to be a 4 cycle to be a hemi.

Now I wonder if the 4 mix is a hemi.

Sent from my SPH-L710 using Tapatalk

?

Hemi, is just a half round chamber with a domed piston.

Don't see what 2cycle vs 4 cycle hast to do with it?

 

[Red97]

Domed piston flat squish band cut into it.

Hard to see, but hemi chamber with a narrow flat squish band.

 

[94BULLITT]

?

Hemi, is just a half round chamber with a domed piston.

Don't see what 2cycle vs 4 cycle hast to do with it?

Hemi is short for hemispherical combustion. The spark plug is at the top in them middle with a valve to each side. That creates a hemisphere. In a 2 cycle you don't have valve to create a hemisphere.

Sent from my SPH-L710 using Tapatalk

 

[RI Chevy]

Maybe a valve-less Hemisphere? There is still fuel to combust and make power.

 

[Red97]

Hemisphere, is half of a sphere.

Just a geometric shape. Dosent care if it has valves or not.

Some chambers are D shaped, cone shaped, Doughnut shaped

 

[X 66 stang347 X]

I can see the 460 has way more power than before.

 

[RI Chevy]

Did run good!