Another chainsaw dyno...

[Backtroller]

Maybe they’re doctoring numbers like VW did with their diesels

 

[Red97]

Maybe they’re doctoring numbers like VW did with their diesels

I don't recall ever seeing any actual echo published numbers. I remember that was saw trolls big arguing point.

All of the big companies can develop their own test procedure to get the hp/tq rating.

Unless you know the correction factors /perameters they used it is very hard to say for sure what the issue is.

Same reason you don't take your car to 5 different dyno shops to see the difference in your changes. You will get 5 different ratings.

 

[pavel408]

Look at the fine print on the hp rating.

Says baised on the epa website rating....

Could have detuned ones to meet emissions, or they are saws abroad.

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

I don't recall ever seeing any actual echo published numbers.

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

All of the big companies can develop their own test procedure to get the hp/tq rating.

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)".

Maybe they’re doctoring numbers like VW did with their diesels

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

edit: Multi-answer

 

[MustangMike]

I'm sure that carb mods have a much bigger impact on modded saws that can benefit more from addl air/fuel.

It would be interesting to see the gains on BGD, TA, Muff Mod and Steel Screen filter vs a fully ported saw. I suspect on some saws a good part of the gain come before the actual porting. The problem is, stock saws have port timing #s all over the place, so the results for one would not apply to the next.

Conversely, I have made some slight changes is just the intake and exhaust porting on ported Asian 660s that resulted in large power increases, so I guess addl power can be hiding in numerous locations!

 

[Red97]

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

Would be fun to dyno a euro spec saw..

From what I could dig up in that iso is had started in the late 70's and the last revision was in 1997, believe it has been replaced now. Really don't feel like buying the complete iso info file. They don't appear to share the info freely.

Could be part if the reason the stihl 660 was so close to book spec?

I am going to guess it has something to do with us emissioms... why is echo about the only one still running carbs, and how can they continue selling a the 680/800 those have to be "dirty" saws by spa standards?

More questions than answers at times.

 

[Stump Shot]

I don't recall ever seeing any actual echo published numbers. I remember that was saw trolls big arguing point.

All of the big companies can develop their own test procedure to get the hp/tq rating.

Unless you know the correction factors /perameters they used it is very hard to say for sure what the issue is.

Same reason you don't take your car to 5 different dyno shops to see the difference in your changes. You will get 5 different ratings.

Just as likely to take 5 of the same model saws out of their boxes and get 5 different ratings ont the same dyno. While today's manufacturing tolerances have tightened up from old, there are still "Wednesday" and "Monday/Friday" saws being made from what I can see. This too would be interesting to see played out on paper.

 

[Red97]

Just as likely to take 5 of the same model saws out of their boxes and get 5 different ratings ont the same dyno. While today's manufacturing tolerances have tightened up from old, there are still "Wednesday" and "Monday/Friday" saws being made from what I can see. This too would be interesting to see played out on paper.

Sure would be fun to know.

Who has five of the same model in the box they want run?

Lol

I do have a pair of stock 261c here.

 

[Stump Shot]

Would be fun to dyno a euro spec saw..

From what I could dig up in that iso is had started in the late 70's and the last revision was in 1997, believe it has been replaced now. Really don't feel like buying the complete iso info file. They don't appear to share the info freely.

Could be part if the reason the stihl 660 was so close to book spec?

I am going to guess it has something to do with us emissioms... why is echo about the only one still running carbs, and how can they continue selling a the 680/800 those have to be "dirty" saws by spa standards?

More questions than answers at times.

If a company has models that beat the "zero" base line for emissions the EPA gives them credit to use towards models that do not, theory being that together they all average out to that "zero" base line. That's the way I understood it.

 

[Stump Shot]

Sure would be fun to know.

Who has five of the same model in the box they want run?

Lol

I do have a pair of stock 261c here.

Over time though as you go you should be able to get a good picture painted as you do more and more saws though.

 

[Red97]

If a company has models that beat the "zero" base line for emissions the EPA gives them credit to use towards models that do not, theory being that together they all average out to that "zero" base line. That's the way I understood it.

Ahh, I had heard something about that.

And in the little bit of reading I could on the iso testing. It made mention of fuel usage, and power testing.

So some of the ultra efficient small saws make up for the bigger saws. De tuning makes sense on some of the other just to make sure you get a pass?

Idk all speculation.

 

[Red97]

Over time though as you go you should be able to get a good picture painted as you do more and more saws though.

Exactly, once a couple of known saws are run. Say stock 372, 461,572,462. That will at least give a number or range for people/builders to shoot for.

Maybe most all ported 70-80cc are 9+hp. Won't know until I run a few others, and if they want to share or not.

 

[Stump Shot]

Ahh, I had heard something about that.

And in the little bit of reading I could on the iso testing. It made mention of fuel usage, and power testing.

So some of the ultra efficient small saws make up for the bigger saws. De tuning makes sense on some of the other just to make sure you get a pass?

Idk all speculation.

If I recall correctly it goes to how they are rated fromwhat usage they are intended as well as how long it's expected service life is as part of the formulation, how it all plays out I'm not sure.

 

[Woodpecker]

If a company has models that beat the "zero" base line for emissions the EPA gives them credit to use towards models that do not, theory being that together they all average out to that "zero" base line. That's the way I understood it.

Yup like carbon credits. At one time a company could also purchase another's surplus carbon credits.

 

[ayoungtexan]

I don't recall ever seeing any actual echo published numbers. I remember that was saw trolls big arguing point.

All of the big companies can develop their own test procedure to get the hp/tq rating.


Unless you know the correction factors /perameters they used it is very hard to say for sure what the issue is.

Same reason you don't take your car to 5 different dyno shops to see the difference in your changes. You will get 5 different ratings.

I think I remember echo posting hp numbers for the 501p, the 355t, and the 620p. But that’s all I can think of

 

[Red97]

Hooray 10mm 044...

 

[mgr1]

Ever tested a 10hp elektro motor as reference?

 

[Red97]

Ever tested a 10hp elektro motor as reference?

No, I don't do electric, and this is set up to run a saw.

I have all of the sae corrections, and the calculation to bring mine back to spec.

Long as the same saw repeats on my dyno day after day. That is all I can do.

So far they have been very close even over the 30-50* temp swings.

I'm not worried about matching published specs. Long as I can repete that is all the matters in the end.

 

[MustangMike]

Would be real interesting to compare a stock 10 mm 044 to a new 462.

Is the 10 a red lever saw? I think they ran the best even though some later 440s were rated hirer Hp due to a wider intake port (when they changed the location of the ring pins on the piston).

 

[Red97]

Both of these are stock well used. The 046 has oem dual port cover with screen.

066 is single port no screen.

 

[Red97]

Mahle jug on the 66.

The 395 is the first husky he has had. Swears up and down the 066 has more power.

Thoughts/theory/guesses?