Porting torque vs hp

[Iron.and.bark]

In the interests of not cluttering up other threads, hp vs torque.

The good thing about this place, is us fella's with differing view points can have these little debates without taking it personal like.

I have seen it mentioned a few times on here that torque is irrelevant in a 2 stroke and HP will always win out.

Now I personally do not agree with that, and my experience (limited compared to that of the other side - Jim you legend) has been that HP has been 2nd fiddle to the torque a saw makes in the same class. This has been in milling, burls and f'ing hard exotic timber.

Now as I understand torque in terms of machinery.

Torque is the ability of a rotating element to overcome a turning resistance.

This word "resistance" to me is the key factor. Unless you meet a level of resistance that can overcome your torque produced, I can see how perfectly valid the statement that HP is king.

Could others please continue on?

 

[czar800]

 

[Mastermind]

Everything depends on the use. There are no right or wrong answers. In soft wood, hi rpm is faster. Rpm and torque = hp.

So, in soft wood, maybe hp wins.

But......in the woods the op mentioned, torque will win. Excessive chain speed will just skate on the hard stuff and even dull the cutters faster.

So, we try to tailor the powerhead to the job at hand.....

 

[CR888]

Well if you look at the formula for HP, you soon realise torque is quite important. (Torque X RPM) ÷ 5252 =HP ...So rpm & torque are pretty important factors in the equation. Many wives tales surround this pretty simple subject. IMO there are many other factors that make HP useful. A 100hp saw that only turns 500rpm ain't gonna win any saw races. How HP is delivered is what's important.

 

[Warped5]

 

[sunfish]

Can't have horse power without torque, so...

 

[TJ the Chainsaw Mechanic]

If you look at steam engines...they all had 100 times the torque as they did horse power. An early Whites steam car produced 25 hp and 600 foot pounds of torque. Crack the throttle and the thing would do 60 MPH faster than a gas engine car! Torque and HP are both important. Not enough of either and the performance goes down. So that's why you add displacement and get the best of both worlds!

 

[exSW]

4400 HP, don't mean chit. How it puts it down is what's important. 900 RPM maybe. I haven't looked lately.

 

[TJ the Chainsaw Mechanic]

View attachment 31697
4400 HP, don't mean chit. How it puts it down is what's important. 900 RPM maybe. I haven't looked lately.

4400 hp and double the torque at least, BUT...that's to drive a Generator which powers the electric motors to move the unit. Tons of factors at play with that beast!

 

[exSW]

4400 hp and double the torque at least, BUT...that's to drive a Generator which powers the electric motors to move the unit. Tons of factors at play with that beast!

It's the torque that flattens the load drawn by the generator. Not really that complicated.

 

[Mastermind]

HP VS Torque.....

 

[Stump Shot]

Everything depends on the use. There are no right or wrong answers. In soft wood, hi rpm is faster. Rpm and torque = hp.

So, in soft wood, maybe hp wins.

But......in the woods the op mentioned, torque will win. Excessive chain speed will just skate on the hard stuff and even dull the cutters faster.

So, we try to tailor the powerhead to the job at hand.....

Not always, sometimes though, slow and steady wins the race. I've seen an old McCulloch 10-10 whoop a new Stihl and a new Husqvarna in hard wood. So we just need more saws. No problems. May we see the new Mastermind Torque series in the future?

 

[CapitaineHaddoc]

Pure HP is probably the best for cutting cookies or for a race saw. For a good worksaw, you need torque and hp's.

 

[jmssaws]

You can't make hp without tourqe.
A saw that has lots of tourqe is cool but why can't it have rpm too?

If you want the chain to go slower then you can slow down the saw or use a small sprocket.

Hp is tourqe and rpm,if your saw has 7ftlbs of tourqe at 9500 and mine has the same but at 11000 then mine has more hp and will out cut the other.

I don't believe there will be much difference in the amount of tourqe between a tourqe work saw or a play work saw, the difference between them is what rpm it's made at,7ft lbs at 9500 will be a lot different feeling and running than 7ft lbs at 11k.

 

[exSW]

If you can take the torque number and move it up the rpm range you've made more hp. But if you lose torque in your build and end up with the same hp number that you started with only at a higher rpm you just built a one trick pony.

 

[Mastermind]

Saws are tricky beasts.....

 

[exSW]

So, in soft wood, maybe hp wins.

But......in the woods the op mentioned, torque will win. Excessive chain speed will just skate on the hard stuff and even dull the cutters faster.

This. I've taken three saws. A 61cc,69cc and a 71cc from different makers,stock. Put the same chisel with the same grind on all three. 20",3/8,.050. Buried them in oak . Had the camera on all three they were within a couple tenths. The only difference was the size of the chips.61cc(fastest rpm wise)dust,71cc(second fastest)chips,69cc(third fastest but had the longest stroke)chunks.

 

[Mastermind]

I build a lot of saws for guys in OZ. They don't want a high rpm saw. Now, I've made the mistake of going overboard on torque too, so I get where Jason is coming from too.

I reckon it's about finding out what sort of saw the customer is looking for.

 

[Mastermind]

Damn Ross.........I finally figured out how to fix your post. LOL

 

[exSW]

Damn Ross.........I finally figured out how to fix your post. LOL

I don't know what happened (Oly lives). Got I fixed now boss.