Sorry, posted that before finishing all posts...If you don't like my math then do it your way, no skin off my back. Us Certified Professional Engineers probably don't know what we are talking about anyway.
I think thats a pretty fair assumption in this case.....Us Certified Professional Engineers probably don't know what we are talking about anyway.
If your where such a smart engineer you wouldnt make statements like the above which are based on false ASSumptions on your part. The differance between a 50:1 and 32:1 ratio is a meager 1%. 4/128=.031=3%, 2.6/128=.023=2%. :angel:Theoretically there should be some power loss with a 32:1 over 50:1 and it is very easy to see why. Gas is what causes the explosion, causing the gasses to expand at a rapid rate and forcing the piston down. While oil does burn it will not burn as hot, clean, or fast which is why we need the gas in there to begin with. By adding the extra oil for a 32:1 mix you are adding 36% more oil or 36% less gass to combust.
VTMechEng said:I have really tried to be nice till now but... This is why I am an engineer and you are not. If you go back to page one and look at what I have put down as a percent decrease you will see it is of OIL and not GAS. The percent increase in gas for my original comparison problem (From 32:1 to 50:1) would be about .00107 gal. Also, I didn't use ratios for this problem but assumed a desired outcome of 2 gal. of gas.
VTMechEng said:I have really tried to be nice till now but... This is why I am an engineer and you are not.
exactly... I remember all the hype and fluff when the Vega came on the scene with all its (then) high tech parts, its lightweight aluminum block. Motor Trend magazine named it "Car of the Year"...when was that, think 1972?. Buddy of mine bought one of the sport models. Wasn't long before he found out that that high tech engine lasted about as long as his original set of cheapo bias ply tires did. His experience, that single experience with the Vega, tainted me for life. I was never as naive since, and it made me a bit more cynical. NEVER buy a car the first year it comes out.. its a crapshoot, even today. The engineers are not dummies, but they still have a bottom line to deal with and there is still built in planned obsolescence, perhaps more today than before, not sure. However, I think the world is just too complex to cover every single circumstance. Look at the reams of data all those NASA engineers came up with telling us that chunks of foam flying into the shuttle wings would do no harm. Well... they did.bwalker said:Engineers where responsible for the Tacoma Narrows bridge and the Chevy Vega!
bwalker said:If your where such a smart engineer you wouldnt make statements like the above which are based on false ASSumptions on your part. The differance between a 50:1 and 32:1 ratio is a meager 1%. 4/128=.031=3%, 2.6/128=.023=2%. :angel:
VTMechEng said:Remember that is was an engineer that made the Stihl 200T and Ford GT40.
VTMechEng said:The fact remains, 2 cycle engines are made to be run with a certain amount of oil and gas at a certain rpm and load. This is mostly governed by their material makeup but also things like port size. Just do what the owners manual says and lets drop this $h!t.
By adding the extra oil for a 32:1 mix you are adding 36% more oil or 36% less gass to combust.
Percent decrease = 36.01%
This is why I am an engineer and you are not. If you go back to page one and look at what I have put down as a percent decrease you will see it is of OIL and not GAS.
The percent increase in gas for my original comparison problem (From 32:1 to 50:1) would be about .00107 gal
If you will please note, I already acholadged that the post you quoted was incorrect.
where a .107% loss in gas could be found for a 2 gal amount
Don't assume things about people, it isn't much better then me assuming you are a hack that tops and uses spikes to prune just because you climb trees.
This is why I am an engineer and you are not
Just do what the owners manual says and lets drop this $h!t.
I tend to agree with you in regards to what determines oil requirements. The problem is the materials used to produce todays saws have changed very little since the days when a 32:1 mix was standard. What I am getting at is the fact emmisions, specificly visable smoke(with the oem dino oil) plays a role in what ratio is speced by the OEM not whats best for the saw. A 50:1 ratio for a severe service use in a chainsaw is laughable as far as I am concerned. Especially when the saw is required to have a restrictive muffler and is run as lean as possible for emmisions purposes.The fact remains, 2 cycle engines are made to be run with a certain amount of oil and gas at a certain rpm and load. This is mostly governed by their material makeup but also things like port size. Just do what the owners manual says and lets drop this $h!t.
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