No turning back now. 044 hybrid

[redfin]

After gettting my first ported saw back from Randy and running a few more this spring I'm all in.

The 44 jug from this is going on one I'm building for my buddy. This gave me perfect opportunity to swap a 46 onto mine.

I bought a machined and ported jug from a fella on here. He has been great answering all my questions.

Meteor piston with .018" squish. 195 psi after 2 tanks through the saw. .020" off the key. Single opening in can opened almost as big as screen size. Both before and after videos saw is tuned to 13.5k.

 

[bryanr2]

that hybrid looks sick! (in a good way)

 

[redfin]

Thanks man, glad to hear your almost back on schedule. Stay away from the painting detail.

 

[mdavlee]

Sounds good on there.

 

[redfin]

I have been wondering about running a ported saw above the manufacturer specs. I don't plan on tuning this saw any higher but after seeing others running these things much higher it got me thinking.

I understand with the higher flow of air your able to increase the mix allowing more oil the reach the important bits but the manufacturer set the wot max rpm for a reason. Are the bearings tolerable to a much higher rpm.

I suppose in the cut even with a strong ported saw the bearings won't ever see a max rpm? Just thinking out loud here.

 

[old-cat]

The whole reason for "porting" is to make the chain speed higher in the cut. Higher compression, more horsepower requires more lubrication

 

[redfin]

The whole reason for "porting" is to make the chain speed higher in the cut. Higher compression, more horsepower requires more lubrication

Yes I do understand that. Its when people tune a saw to let's say 14.8k when the saw munufacturers max rpm is 13.5k.

 

[old-cat]

Tuning by tach only applies to unmodified engines. The way to properly tune is in the cut, max load, cleaned up sound.

 

[CapitaineHaddoc]

Since i work with ported saws, i just put more oil in the mix (33:1), then i tune the saw by ear, and if it's clearly 4-stroking at WOT, it is fine for me (just have to be careful if the coil is limited)

 

[Chris-PA]

I have been wondering about running a ported saw above the manufacturer specs. I don't plan on tuning this saw any higher but after seeing others running these things much higher it got me thinking.

I understand with the higher flow of air your able to increase the mix allowing more oil the reach the important bits but the manufacturer set the wot max rpm for a reason. Are the bearings tolerable to a much higher rpm.

I suppose in the cut even with a strong ported saw the bearings won't ever see a max rpm? Just thinking out loud here.

The max WOT has one and only one meaning: it is a way of setting the fuel mixture on a factory stock saw.

A chainsaw carb does not deliver a fixed fuel/air mixture like most other carbs do. Instead, as the air velocity (rpm) increases at WOT, the mixture gets richer and richer. So assume you have the mixture correct at lower rpm in the cut. If you lift the rpm and air velocity go up, and the mixture gets so rich the saw misfires (4-strokes). If you remove all load it will rev to a point where the mixture is so rich it won't rev any higher (assuming the ignition is not limited). You can control that point solely by turning the mixture screw.

It's crude, but there really isn't any other convenient way to for the manufacturer to tell people how to set the mixture. What they do is to set up a stock saw with the mixture set properly under load, and then see what rpm it gets to WOT no load. If you then duplicate that WOT no load setting, the mixture should be correct at lower cutting rpms.

But if you have modified the saw in any way, that relationship between no load and lower rpm fuel/air mixture is out the window. It is far better to set under load it by listening for the "4-stroking" as you lift - and then you can forget about the no load WOT rpm value as it means nothing.

 

[MustangMike]

Even the stock saw is very strong!

 

[redfin]

The max WOT has one and only one meaning: it is a way of setting the fuel mixture on a factory stock saw.

A chainsaw carb does not deliver a fixed fuel/air mixture like most other carbs do. Instead, as the air velocity (rpm) increases at WOT, the mixture gets richer and richer. So assume you have the mixture correct at lower rpm in the cut. If you lift the rpm and air velocity go up, and the mixture gets so rich the saw misfires (4-strokes). If you remove all load it will rev to a point where the mixture is so rich it won't rev any higher (assuming the ignition is not limited). You can control that point solely by turning the mixture screw.

It's crude, but there really isn't any other convenient way to for the manufacturer to tell people how to set the mixture. What they do is to set up a stock saw with the mixture set properly under load, and then see what rpm it gets to WOT no load. If you then duplicate that WOT no load setting, the mixture should be correct at lower cutting rpms.

But if you have modified the saw in any way, that relationship between no load and lower rpm fuel/air mixture is out the window. It is far better to set under load it by listening for the "4-stroking" as you lift - and then you can forget about the no load WOT rpm value as it means nothing.

I believe that's where my thinking was off regarding max rpm. I was thinking it was more for the failure of components and not for max HP at given rpm.

 

[farmer steve]

so i can run that at our GTG next spring?

 

[redfin]

Absolutely Steve.

 

[mdavlee]

I like to tune a ported saw by ear and reference it with a tach. I have tuned some and they were over 14.5k by ear and they were tuned down to around 13.7k. I just don't see the need in the extra rpm for a work saw.

 

[redfin]

I was thinking about Chris' explanation and now I'm wondering what the manufacturers use as a baseline for altitude.

The largest diffference I have run my saws was roughly 1800' but I did notice a change.

 

[redfin]

I picked up a couple new parts for this saw from some guys on here. 20" lw Sugi and a 3/4 wrap. I still need to get another set of Metals dogs, I really like them on my 660.

 

[cgraham1]

I picked up a couple new parts for this saw from some guys on here. 20" lw Sugi and a 3/4 wrap. I still need to get another set of Metals dogs, I really like them on my 660

Looks good! You just need the tall clutch cover now! I'm saving mine, along with another 3/4 wrap for my 044 project.

 

[redfin]

I forgot about this vid until was loading another tonight.

 

[showrguy]

I forgot about this vid until was loading another tonight.

a backhoe sure makes firewooding soo much easier, does'nt it...
mine doubles as my hydraulic log lift for my new supersplit-electric,,,,,,,sweet///