I call B.S. on Stihl. My dyno doesn't lie. MS 461 is king over MS 660

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To me, they are what put and keeps man on top the food chain.
Tool making was an important step - but I think most anthropologists would consider the written language the critical step.
The printing press probably accounts for more of man's advances than any other tool.
 
Troll, thanks for the info, your post was from 2005. That HP # is the same as what they came up with for the 460. However, with rounding to the nearest tenth in both kw and kg, it is tough to compute accurate #s.

HH, I think I can answer your question in part. Often high torque diesel engines have a limited RPM range. For max performance on a high power gas engine, the shift points will keep the engine between max torque and max HP, and max HP will be in a much higher range. The design of the diesel is more intended the reach and hold a certain RPM, not provide rapid acceleration. Conversely, the high performance gas engine rapidly builds power approaching max Hp, launching you like a slingshot.

MM, no wonder you are so successful. Similar to above, for chainsaws the important thing is to maintain max power in the cut, not provide rapid acceleration or power in an RPM range that will not be used (high or low). When your saws provide more power at a slightly higher RPM range than a stock saw, cut times will increase dramatically and it will be easier to maintain that RPM range under various conditions (the additional power will better resist slowing).
 
Tool making was an important step - but I think most anthropologists would consider the written language the critical step.
The printing press probably accounts for more of man's advances than any other tool.

The more sophisticated we get, the more you are correct, but if early man did not develop weapons to protect himself from dangerous beasts and harvest food, we would likely not need the printing press today. Some studies also indicate that Man's relationship with the dog may go back a long way. That would give them a big leg up in identifying potential threats and finding / catching game.
 
Most of the time I see that a modern saw engine will run at plenty of RPM just because of the design. (Transfer design, tight case capacity, etc)

Because the RPM is there already, I look for ways to improve the power in the working range.
I've come up with a exhaust height to displacement rule that I adhere to. It seems to be working very well. I believe that if the exhaust is too high (and of course there are gonna be exceptions) the engine will make peak power at an RPM that is unattainable in the cut. So I shoot for maximum power at working RPM.

I realize that is a quick and dirty answer, but you'd have to see the advances in design compared to less modern designs that have been made in the last couple of decades to get what I'm talking about.
Is the displacement rule in relation to the exhaust outlet, crankcase displacement? Sorry for picking the mind but ive been dabbling with mild porting and interested
 
That HP # is the same as what they came up with for the 460. However, with rounding to the nearest tenth in both kw and kg, it is tough to compute accurate #s.

True enough, calculations made on rounded off numbers may lead to "funny" results - but does that slight inaccuracy really matter?
 
Tool making was an important step - but I think most anthropologists would consider the written language the critical step.
The printing press probably accounts for more of man's advances than any other tool.

It's true wherein we discuss advancements made as a civilization; as printing is what enabled us to make contracts and laws. The law of the jungle will ultimately trump that. Chainsaws and gunpowder are a pretty good buffer.
 
I think this may be worthy of cluttering my sig for a few days. ;)

Seriously though, maybe you guys can clarify this for me. If 'torque' is a measurement of how much power the engine produces and HP is just an extrapolation of torque and RPM, why couldn't a diesel with gobs of torque and a variable ratio transmission that keeps the engine at peak torque rpm during acceleration stomp a peaky gas engine with much less torque but more hp?

I guess a simpler way of saying it is.. if torque is what does the work, why does the rpm the engine has to run to produce it matter? The engine with the most torque should win if it's geared correctly.


Sure, I can at least try to help you.

First, torque by itself means NOTHING! For example, consider a torque wrench 1 foot long mounted horizontally where you hang a 10# weight at the end of the bar. The other end of the bar is fixed and cannot move! At the point where the bar is fixed, there will be a force (TORQUE) of 10 pound foot.

Increase the bar length to 5 feet with the same 10# pounds mounted on the extended end and there will be 50 pound foot of force at the secured end or a TORQUE of 50 pound foot. Notice that TORQUE by itself means NOTHING!

Now consider HP which whose name was adopted by James Watt when he attempted to show how powerful his steam engine was by relating it to horses. He said 1 horse can raise 33000 pounds 1 foot in 1 minute or 550 pounds foot in 1 second. Now people could understand how horsepower could related to doing work.

Foggy
 
I build saws that make torque. I don't look for additional unloaded RPM at all.

My reasoning is that by making more power.....the engine will hold more RPM in the cut. At about 10,500 - 11,000 RPM.

Now, here's the thing. My engines don't do well in cant races....even with taller gearing.

Discuss?

:laugh:




Tough to find the KS 066 top ends these days.....just stick with the 064 top end if you wanna really fun saw.
from what i have seen, there is a big difference between a work saw that i would use as compared to a dedicated cookie cutter. they never are dogged in for one thing.
when guys say don't use the dogs, i get tickled.............hold back a large saw in the back cut all day and see how that works lol.
i love torque in a saw. any who has used big saws years ago to fall will tell you the same.
 
Anything you could tell us about how saws are chosen for testing, how many saws are tested, or anything else about the process would be interesting to at least myself. I've considered those to be quite independent tests - but without any real knowledge of their processes. I at least put more weight in their results than spec sheets.....
.

Yes, all that would be interesting to know - and the info is conspicuously abcent.....
 
The US delivered saws are definitely Dyno'd in Germany. That's where the in-house testing is done. The Virginia Beach facility doesn't have that type of equipment nor do they need it. So that all means that the saw specs advertised in the US literature may/may not be from units tested which are equipped with the US specified performance bottlenecks. If I was the Germans, I'd keep the best ones and tell us to make our own. It's what we should do anyway. We could call them, "Poulan" or sumthin'.
 
The US delivered saws are definitely Dyno'd in Germany. That's where the in-house testing is done. The Virginia Beach facility doesn't have that type of equipment nor do they need it. So that all means that the saw specs advertised in the US literature may/may not be from units tested which are equipped with the US specified performance bottlenecks. If I was the Germans, I'd keep the best ones and tell us to make our own. It's what we should do anyway. We could call them, "Poulan" or sumthin'.

That's on my bucket list when I hit the lottery, see if I can hostile takeover poulan back from husky.
 
from what i have seen, there is a big difference between a work saw that i would use as compared to a dedicated cookie cutter. they never are dogged in for one thing.
when guys say don't use the dogs, i get tickled.............hold back a large saw in the back cut all day and see how that works lol.
i love torque in a saw. any who has used big saws years ago to fall will tell you the same.

If I had to hold the dogs off the log all day after having my saw ported........someone would be in trouble. :chainsaw:

Is the displacement rule in relation to the exhaust outlet, crankcase displacement? Sorry for picking the mind but ive been dabbling with mild porting and interested

No, it's related to cylinder displacement.

If anyone wants to try the numbers I use, just contact me. I'll gladly share what I use, but would rather not post that sort of stuff in the open forum anymore.

Too many people want to argue about that crap.
 
I was hoping that someone would be able to explain it to me. I can't wrap my mind around it. Doesn't make sense.


There's so much I don't understand.

That's why I just do saws for work. I have a pretty good idea how to make those units perform.

Cant cutters are a whole different ball of wax.
 

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