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070-088-076-090 torque comparisons

Discussion in 'Chainsaw' started by harrygrey382, Apr 25, 2008.

  1. harrygrey382

    harrygrey382 Addicted to ArboristSite

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    Now I know paper figures are by no means everything, but I have been looking at them none the less. It seems to be, the 070 has significantly more torque than the 076, and the same as an 088 (well, 0.1Nm less), while the 090 is quite a bit higher. My sources are the test reports in the reference links for the 880, and the service manual (thanks dibbs) for the 070, 090 and 076.

    What I'd like to know is, why is the 070 much higher than the 076, even thought the 076 has a (2mm) longer stroke? why is the 076 so poor compared to all of them? Why isn't the 088 much more torquey than the 070? Do people's practical observations confirm/blow this comparison?

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    Last edited: Apr 25, 2008
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  2. SawTroll

    SawTroll Information Collector

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    Just for the record, the hp number varied from 6 to 6.5 for the 070, and from 8.5 to 9 for the 090.

    I don't know if the max torque changed, as well - but it is likely......

    .....or it may just have been a paper exercise, or marketing......



    :dizzy:
     
  3. harrygrey382

    harrygrey382 Addicted to ArboristSite

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    hmm, well that might make it more believable. But the HP figures are reasonable - it's the torque that bamboozals me, it'd have to vary by a very large amount for the 070 to fit the trend. Also, I'd thought the 076 wasn't quite so far behind the 088...
     
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  4. Lakeside53

    Lakeside53 Stihl Wrenching

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    Good work! I'll dig around for the 056 numbers...
     
  5. belgian

    belgian Addicted to ArboristSite

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    I am surprised too for the 076 numbers as it was reported to be a torque monster... I just found one in like new condition and was ready to pull the trigger on it....hmmmm what to do....???:confused:
     
  6. Lakeside53

    Lakeside53 Stihl Wrenching

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    buy a new 880? lololol

    It is a torque monster... but its all relative...
     
  7. belgian

    belgian Addicted to ArboristSite

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    I have a 084 already....heck, that one is not listed here....:popcorn:
     
  8. blsnelling

    blsnelling Site Sponsor

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    Your chart is very insightful. I'm a visual type learner and that really puts it in perspective.
     
  9. Jacob J.

    Jacob J. Tree Freak

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    There are several differences in the three engines.

    070= Flat, wide ports; larger mixing area; heavier crank and piston; heavier flywheel and clutch; straight intake vertical design; large Tillotson HL carburetor.

    076= Long, 'lateral' ports; horizontal design; makes power at higher RPM; direct crankcase intake/mixing area; smaller Tillotson HS carburetor.

    088= Makes power at much higher RPM; much lighter piston-crank-flywheel-clutch; straight intake vertical design; blend of port shapes and timing; smaller mixing area; aggressive ignition timing.

    There's a reason the 076 engine is used for the TS-760 cut-off saw. Different engine designs= different applications.
     
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  10. SawTroll

    SawTroll Information Collector

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    Yes, but it would have been fun to see the Jonsereds 111 torque numbers in there, and the Husky 2100/2101/298......


    I also notice that the MS361 has the best hp/cc ratio on the list - LOL!

    In addition, I will say that the "double torque" of the 090G is highly irrelewant, as it only is at the chain, not at the crank........
     
    Last edited: Apr 25, 2008
  11. djmercer1

    djmercer1 ArboristSite Operative

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    i like what youve done, but im not sure what a hp(torque):cc ratio really means when incorporating different engine designs. as jacob said different engine design would likely have significantly different ratios.

    id think that if you got the numbers for 3,4 or 5 saws with the same engine design(ie 041, 051 and 076) and plotted torque vs hp, that those ratios should plot in a near straight line until the curve flattened(maybe not possible to show though with the limited displacement variables of saws) out to identify the optimal size for that engine design. if you had another set of numbers for a saw in the 070/090 family you may find why the 070 looks out of place, if it is at all. also, the other factor may be where and how the torque was measured. if it was measured at the crank or the clutch could have some bearing on it, maybe.

    also harry, not to start a fight, but didnt i send you the 051/076 service manual( i got to get me my dues, just joking...)?
     
  12. djmercer1

    djmercer1 ArboristSite Operative

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    i could tell you where there is one with about 10-15 hours on it for free, but youd have to dive to about 20m to get it...we lost one last winter:cry:
     
  13. rxe

    rxe AboristSite Guru

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    Hmmm. I have an 880, an 090 and an 070.

    The 090 is unstoppable in pretty much anything. Load up a "grabby" chain, lean on the bar and even in solid oak, it just keeps on going.

    The 880 cuts quicker for a given bar length in my experience, but just like any normal chainsaw, you can bog it pretty easily. It is revving a lot faster than the 090 - 10K rpm maybe, as opposed to 7000 for the 090.

    The 070 is somewhere in between. Not that fast, but generally unstoppable.

    I've got something else to try out now. I bought a NOS Contra cylinder and piston for my restoration work. I pulled it out of the box and thought "that looks bigger than I expected". It would appear that I have a 137cc Contra "Super" item. Stick that on the graph next to the 090! :)
     
  14. belgian

    belgian Addicted to ArboristSite

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    Hmmmm, sounds good rxe, you lucky dooog ...:clap: :clap:
     
  15. hoss

    hoss Addicted to ArboristSite

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    Maybe mine is unusually strong but the 075 is one of the torquiest sumbiches I have ever used. I have most of the big stuff you hear about (2100 husky. 084 stihl, 090 stihl 075 stihl, 056magII stihl, 125 mac, 750 homie + lot's more)
    and the 075 is one of the hardest saws I own to bog in any cut. I have 2 075's and they both run this well. I would say that aside from a gear drive the 075 is equal to my 084's ( torque not speed) and behind only the 090. Once I was ripping a 36" oak round in half and had cut the guide teeth on my chain just a bit too low and the 075 grabbed and stood that big round up on it's side. All of these saws are stronger than anything most people will ever run into though. Most of what I cut is large hardwood and this is what I have noticed as I use these saws in rotation. I think that the 125 and 075 are pretty close too from a torque standpoint.
     
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  16. KindlingKing

    KindlingKing ArboristSite Operative

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    What about the 066 at 7.7 hp? Did it generate more torque than the MS660 at 7.0 hp? My MS 660 is sporting the dual port muffler, which I'm told brings it in at about 7.7 hp... does the torque go up proportionately with the hp increase? Now I'm really curious to see what numbers Lakeside comes up with for the 056 magII...... I've heard its got a lot more torque. I just gotta know.... I've never run one before.:chainsaw:
     
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  17. harrygrey382

    harrygrey382 Addicted to ArboristSite

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    Great, Really want them up there - all three of them
    no data for that...
    yeah really want to the 111 numbers up there, don't know about the others. Anyone got a Jred 111 manual?
    Yes you did - full credits, that manual started it all! Point taken about all if them, that ratio was just an afterthough, I could post the table that includes the others (husky, dolmar)
    may well be, if someone has torque figures i'll put them up...
     
  18. harrygrey382

    harrygrey382 Addicted to ArboristSite

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    hmm, this is what I was expecting somone to say - I thought I'd heard before what a torque monster the 075 was. No doubt they are very torquey, Maybe the 088 is more than the 084 though... I want someone to say these numbers are wrong cos I've gone the way of the 075. But you didn't have an 070 in there, and now I want one!
     
  19. SawTroll

    SawTroll Information Collector

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    The original "Red Light" 066 was listed at less hp than the later ones (and the 660), but then there were the magnum muffler......
     
  20. harrygrey382

    harrygrey382 Addicted to ArboristSite

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    ok, we need a collective effort here - can everyone with service manuals for saws not listed post the saw torque and hp ratings (with RPM) - would be god to get various 066s up, and the 084, and previously mentioned old monsters
     

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