Dyno #'s for Husq Stihl Dolmar Solo

[one.man.band]

Max. HP and Max. TQ @ RPM

Link: Geprfte Motorsgen

Saws Tested:
Dolmar: PS: 420, 4605, 5105, 6400, 7300, 7900
Huqvarna: 346XP, 353, 357 XP, 359, 372 XP, 390 XP, 576 XP
Solo: 665, 675, 681
Stihl: MS: 192, 241, 260C, 260, 280, 290, 311, 362, 390, 391, 440, 441, 650, 660, 880

 

[chopperfreak2k1]

very cool! thanks

 

[Brian VT]

Well, I guess that ends the 5105/346/260 debate, right ? LOL

 

[tallguys]

Well, I guess that ends the 5105/346/260 debate, right ? LOL

Now THATS funny! :hmm3grin2orange::hmm3grin2orange::hmm3grin2orange:

 

[WoodChuck'r]

Horsepower numbers are all well and good but they don't mean anything IMO.

Chain type, chain condition, wood type, wood condition, sprocket size, bar length, air filter type, air filter condition, and carb settings (among other things I haven't listed) are all factors in what makes a saw cut the way it does.

Put a beat and burned up chain on a 7900, then put a razor sharp chain on a 346 and you'll see the 346 cut better and faster regardless of how much more horsepower the 7900 has. Once again I say, higher horsepower does not equal a stronger saw and a stronger saw does not result in higher horsepower. Change the conditions and you'll see why horsepower ratings are so worthless. Unless of course, you just feel like doing some spec reading about a powerhead in brand new condition, there's no reason to focus on or care about horsepower ratings at all....

I don't ever care about or pay attention to horsepower numbers and factors like the ones I listed are precisely why....

 

[splitpost]

Horsepower numbers are all well and good but they don't mean anything IMO.

Chain type, chain condition, wood type, wood condition, sprocket size, bar length, air filter type, air filter condition, and carb settings (among other things I haven't listed) are all factors in what makes a saw cut the way it does.

Put a beat and burned up chain on a 7900, then put a razor sharp chain on a 346 and you'll see the 346 cut better and faster regardless of how much more horsepower the 7900 has. Once again I say, higher horsepower does not equal a stronger saw and a stronger saw does not result in higher horsepower. Change the conditions and you'll see why horsepower ratings are so worthless. Unless of course, you just feel like doing some spec reading about a powerhead in brand new condition, there's no reason to focus on or care about horsepower ratings at all....

I don't ever care about or pay attention to horsepower numbers and factors like the ones I listed are precisely why....

And the major contributing factor...........THE OPERATOR

 

[mdavlee]

It is nice to see an unbiased test of the ratings. It shows the stihls almost dead on the what they rate their saws and husky is a tiny bit behind. The 5105 and 346 is interesting. I don't care how much better you say a 346 handles but that test shows how gutless they really are. I hope the 550 is a lot stronger as I would rather have a stihl 261.

 

[Brian VT]

And the major contributing factor...........THE OPERATOR

Ok, so you give that same OPERATOR those saws. What does that do to the results of the test ? Nothing.
I think what you're saying is that they're all good saws. I don't think anyone could disagree with you.
If someone says one is better than the other, they're wrong. There's too many variables involved for someone to make that claim.
If someone says that the 5105 has more power than the 346xp and 260, they're right. And they have data to back it up.

 

[Stumpys Customs]

I'd love to have a dyno to test & tune with. You all are right about chains & operators. But to be able to see on paper what hp & tq a saw is making on a graph would be priceless. I could change one thing at a time to see what works.

 

[splitpost]

Ok, so you give that same OPERATOR those saws. What does that do to the results of the test ? Nothing.
I think what you're saying is that they're all good saws. I don't think anyone could disagree with you.
If someone says one is better than the other, they're wrong. There's too many variables involved for someone to make that claim.
If someone says that the 5105 has more power than the 346xp and 260, they're right. And they have data to back it up.

All very true, but like the post says,with all the different variables and the operator being the biggest, horsepower is only part of it ,lets take the 441,now two identical saws but two different operators,one will always finnish before the other in a race and thats before you start throwing different chains and sprockets,fuel mixes etc, in there,the list goes on

 

[Brian VT]

...horsepower is only part of it

I agree, but this thread is about tests under controlled conditions. No opinions, experience, skill, or personal preferences involved.

 

[splitpost]

I agree, but this thread is about tests under controlled conditions. No opinions, experience, skill, or personal preferences involved.

Agreed,but we all know that opinions, experience, skill, or personal preferences will always be the deciding factors for a saw purchase,its just human nature,tests or no tests

 

[one.man.band]

by not counting differences in operator, chain, wood etc. .... could any conclusions be made on how a saw will perform, just based on the dyno peaks for power and torque?

case in point: (using peak power and torque values at respective RPM #'s from the linked site).

Husq 346XP Displacement 50.1cc; Bore 44.3mm; Stroke 32.5mm
10500 RPM: Max Power = 2.5 kW; Torque = 2.3 Nm
7000RPM: Power = 2.0 kW; Max Torque = 2.7 Nm

Dolmar PS 4605 Displacement 46.5cc; Bore = 43mm; Stroke =31mm
10000 RPM: Max Power = 2.5 kW; Torque = 2.4 Nm
6500 RPM: Power = 1.9 kW; Max Torque = 2.7 Nm

Dolmar PS 5105 Displacement 50.0cc; Bore = 45mm; Stroke = 31mm
10200 RPM: Max Power = 2.9 kW; Torque = 2.7 Nm
6300 RPM: Power = 2.1 kW; Max Torque = 3.2 Nm

i do not own any of the above saws..... the RPM peaks for max power and torque are similar. would expect them all to be very similar in use, to be peaky, and lose RPM's in the cut quickly because of the 3500 to 4000 RPM differences between peak power and peak torque. is this true?

case in point:

Stihl MS 260 Displacement 50.2cc; Bore = 44.7mm; Stroke = 32mm
9600 RPM: Max Power = 2.6 kW; Torque = 2.6 Nm
6300 RPM: Power = 2.2 kW; Max Torque = 3.1 Nm

the Peak Power and Peak Torque of the Stihl are equal (very close) to the Dolmar. the difference is the fact that the Stihl saw does this at lower RPM's. to me, that would indicate a less peaky saw in the cut than the saws above. the Stihl saw has Peak RPM of Power and Torque figures about 3000 RPM apart, lower, but close to the above saws. could it be said that the Stihl performs better at lower RPM's. it would seem that over-revving would be of less benefit to this saw. does this saw lose RPM's even faster in the cut than those listed above?

 

[justtools]

Horsepower numbers are all well and good but they don't mean anything IMO.

Chain type, chain condition, wood type, wood condition, sprocket size, bar length, air filter type, air filter condition, and carb settings (among other things I haven't listed) are all factors in what makes a saw cut the way it does.

Put a beat and burned up chain on a 7900, then put a razor sharp chain on a 346 and you'll see the 346 cut better and faster regardless of how much more horsepower the 7900 has. Once again I say, higher horsepower does not equal a stronger saw and a stronger saw does not result in higher horsepower. Change the conditions and you'll see why horsepower ratings are so worthless. Unless of course, you just feel like doing some spec reading about a powerhead in brand new condition, there's no reason to focus on or care about horsepower ratings at all....

I don't ever care about or pay attention to horsepower numbers and factors like the ones I listed are precisely why....

Sounds like someone didnt like the results.

 

[WoodChuck'r]

Sounds like someone didnt like the results.

Nice try at a low blow but you fail.


I never looked at the HP ratings in the link actually. Like I said, I don't really care about them. My saws usually go under the knife anyways - even if I cared about HP ratings I'd fark'em up from sending them off to the builder....

What the saw can do in a cant tells the tale, not HP ratings. :msp_thumbup:

 

[TK]

To enforce a point - not all lies in the power. While HP is a good basis to use for power, and typically is the selling point for anything with an engine, it certainly does not tell the tale of performance.

Why are there drag races? Because you don't just dyno the engine and declare a winner.

How an engine makes that power is another big factor. Take the 576xp for example. You can purchase one with a standard carburetor. You can purchase one with an AutoTune carburetor. They are rated for the same HP. The advanced technology used in the AutoTune setup gains more usable power out of those ratings. Is it going to be a huge difference? No, but there is a difference - even though the rated power is the same.

Let's say you take a saw and mod it. Then you can also dyno it. Do you really care if it went from 5HP to 8HP if the cut time through the same log was only decreased by 1 second whereas if the saw the goes from 5HP to 6HP decreases its time by 2 seconds?

 

[steve316]

dyno testing

there is no better way to tell what your porting is doing to the power ban than with a dyno.the more varibales you can remove the better.Steve

 

[sachsmo]

Hmmmm.

 

[justtools]

I do believe their is more to a saw than hp ratings. But I do believe that hp is in the top 3 things a guy wants in a saw, Like reliability, ergonomics, Hp would round out my top 3 things I look for in a saw.

 

[WoodChuck'r]

I do believe their is more to a saw than hp ratings. But I do believe that hp is in the top 3 things a guy wants in a saw, Like reliability, ergonomics, Hp would round out my top 3 things I look for in a saw.

Makes sense. Even though I have no interest in HP ratings, they probably do play a larger part than most might know when it comes to saw sales. Goes back to the comment I made about researching powerhead specs. Whether someone's a saw guru or not - they're gonna treat it like anything else they're gonna purchase and find out as many spec numbers as they can.....