Another chainsaw dyno...

[cuinrearview]

 

[Bigmac]

There were huge production tolerance differences in the o66/660s Have personally seen .019-.035 squish In completely stock saws, and compression ranging from 145 to 175 on perfectly fresh saws, Those factories saws at .019 175 psi are pretty darn good runners

 

[Backtroller]

In Europe Echo states "Maximum shaft brake power (ISO 7293) 3.32 kW", which is the same as 4.4 hp listed in US.


Not in US, but in Europe they have to publish the power numbers, see manuals e.g. in https://www.echotools.com/en_us/support/manuals


They indeed can, but there is the ISO. I don't see that in Husqvarna manuals, but Stihl announces "Engine power to ISO 7293: xxx kW (xxx bhp)".


This is the opposite case - VW wanted lower emissions, but why would Echo want lower power?

edit: Multi-answer

My point is that companies are often not honest with numbers. Look at published weights for some saws

 

[Red97]

My point is that companies are often not honest with numbers. Look at published weights for some saws

If you look at the echo link, they call out stihl/husky for being off on the published weights.

 

[Red97]

https://opeforum.com/threads/10-mm-044-ish.4604/

Here is the 044 build.

 

[Red97]

Well the 066 vs 395 graph is done...

 

[NPKenny]

Well the 066 vs 395 graph is done...

And....

 

[Red97]

And....

Now the 044/046 graphs are done too.

 

[Red97]

 

[NPKenny]

This is a lot to digest.

I have no sense for which saw would be more useful between the 066 and 395. The 395 has a huge HP advantage overall and early, but falls on its face in the RPM range that I think I would normally cut in.

Thank you for sharing all of this.

 

[Bigmac]

View attachment 243866
View attachment 243867

Super interesting, so that 066 has way less peak power but more cutting rpm, in smaller wood the 066 would be faster, interesting! And both the 044 and o46 have similar power to that 066.

 

[Red97]

The 046 is rated at 6.1 hp.

This one is at 6.3hp with the dual port / screen. That one seems really close to book

The 044 was rated at 5.1
Add some mild porting, it is at 6.5 now.

Need to get the stock high hour unit on too see what it puts out .

 

[NPKenny]

And that 10mm 044 is really something. Slightly larger than a 361 and hanging in there with an 066. Off to read the build thread...

 

[Red97]

And that 10mm 044 is really something. Slightly larger than a 361 and hanging in there with an 066. Off to read the build thread...

It is not complete lol

Didn't remember till I linked it.

Nothing major,

.025 off the base set squish.
Raise exhaust, widen a bit and same on intake. Blend lowers. Dual port cover. Timing advance.

Mild.

 

[Red97]

Super interesting, so that 066 has way less peak power but more cutting rpm, in smaller wood the 066 would be faster, interesting! And both the 044 and o46 have similar power to that 066.

See this is where it gets fun... do you run a 8pin on that 395 and let it hog at 9k?

And a 7 on the 066 at 11k? Then what?

Can't wait till I get this stock 395 on the dyno.

 

[ayoungtexan]

I wish I had trees to justify a 10mm 044.

 

[NPKenny]

I wish I had trees to justify a 10mm 044.

What exactly does "justify" have to do with a chainsaw???

 

[Agent Smith]

I wish I had trees to justify a 10mm 044.

Just get one. You'll find wood to play in

 

[ayoungtexan]

What exactly does "justify" have to do with a chainsaw???

An 044 would be considered overkill for the size wood that I cut, usually around 14” diameter

 

[Red97]

I wish I had trees to justify a 10mm 044.

Have 3 more saws coming to build hybrids out of.

2 red, 1 orange.