Octane question

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After reading a thread like this I wonder is there anything you guys can run without screwing it up ?

Octane booster works fine. It is an anti-knock agent, period.

If 87 is all you can get octane booster will get that rating up. That is all it ever was anyway, an anti knock rating.
 
If it is really air tight, it would stop it. But plastic cans still allow some evaporation due to perfusion through the plastic. Still, I use them because they don't rust. There can be some oxidation of fuel from the oxygen in the vapor space, but it will be minimal in an air-tight container.
Metal Coleman fuel cans are ideal to store mix in, no air no light. Similar used solvent cans from auto body shops. They may even have 5-gal.

Best is they are free.
 
I run all professional series stihl saws with stihl ultra oil and I use the highest grade pump gas i can find ethanol or not. Higher octane burns hotter and faster. Leaving your saw cooler. Ask any mechanic. My uncle was a dealer and mechanic in Mississippi. If I'm going to pay $1600 for a saw I'm not going to go cheap on oil or gas
I agree, to a point. Spending an extra $1/gallon to get E-free, 91 octane? Makes sense. Spending $3+ extra per gallon for something like 100LL or premium pump gas with an octane booster? Doesn't make as much sense (at least for me). We spend many times more in fuel in our saws during their lifespan than the saw itself. It makes sense to minimize our fuel and bar oil cost, since that's really where our money is going.

Please refer to this thread for more info on the cost of fuel during a saw's lifespan. This thread doesn't have perfect calculations, but it gives you an idea.
 
Metal Coleman fuel cans are ideal to store mix in, no air no light. Similar used solvent cans from auto body shops. They may even have 5-gal.

Best is they are free.

I have a couple trufuel quart cans that I always fill up after I mix fuel. They will fit inside my saw case.
 
After reading a thread like this I wonder is there anything you guys can run without screwing it up ?

Octane booster works fine. It is an anti-knock agent, period.

If 87 is all you can get octane booster will get that rating up. That is all it ever was anyway, an anti knock rating.
Octane boosters have a very minimal effect on actual octane rating. They also have downsides like combustion deposites or degrading rubber and plastics depending on which one your using.
 
Correct. Higher octane burns slower to prevent detonation, which is combustion so fast it is essentially an explosion. High octane fuels contain larger amounts of aromatic hydrocarbons such as xylenes and mesitylenes
NONE of that is true. Pump fuel varies by the hour when it's produced, but all of it wether 87 or premium has a similar flame speed and energy content.
Detonation is actually prevented by things like squish bands geometry, which speeds up combustion.
No pump fuel sold in the US has high levels of Xylenes. All refineries have units that remove BTX.
 
NONE of that is true. Pump fuel varies by the hour when it's produced, but all of it wether 87 or premium has a similar flame speed and energy content.
Detonation is actually prevented by things like squish bands geometry, which speeds up combustion.
No pump fuel sold in the US has high levels of Xylenes. All refineries have units that remove BTX.
We analyzed gasoline samples by GC/MS. We identified and quantified each and every peak in the chromatagrams. Xylenes are indeed present, more so in higher octane fuels. There was also toluene and trace amounts of benzene.

By trace I mean near baseline.

Higher octane does burn slower in a more controlled manner. It has more high molecular weight hydrocarbons in addition to aromatics.

Don't believe me? Put a match to n-pentane (stand back not too much!) and compare that to n-decane

Energy content of two molecules of n-petane is near the same as one of n-decane. Ever study thermodynamics/physical chemistry?
 
We analyzed gasoline samples by GC/MS. We identified and quantified each and every peak in the chromatagrams. Xylenes are indeed present, more so in higher octane fuels. There was also toluene and trace amounts of benzene.



By trace I mean near baseline.



Higher octane does burn slower in a more controlled manner. It has more high molecular weight hydrocarbons in addition to aromatics.



Don't believe me? Put a match to n-pentane and compare that to n-decane
I work in oil refining. In the last 20 years refiners have invested billions of dollars into equipment to remove BTX. Is there some still present? Yes, but at very minimal levels. The days of jacking up aromatic(BTX) levels to increase octane is long gone and the EPA mandates this.
Higher octane fuels do not burn slower.... in fact if they did it would lower their octane rating. Detonation takes heat and time to manifest itself. Anything you do to slow down combustion increase the risk of Detonation.
Putting a match into a hydrocarbon doesn't prove anything. Detonation isn't normal combustion, it's abnormal combustion.
And yes I have taken both organic and inorganic chemistry in HS and college. You are talking about theory and I am telling you that in practice premium and 87 have the same energy content depending on the time you take the sample. The thing you must consider is there is no recipe or formula for gasoline. It's a chemical soup of a variety of components that are constantly blended to hit a performance specification. Some refinery streams are poor quality and some are high quality, but at the end of the day they all will be blended and nothing is wasted.
 
I run all professional series stihl saws with stihl ultra oil and I use the highest grade pump gas i can find ethanol or not. Higher octane burns hotter and faster. Leaving your saw cooler. Ask any mechanic. My uncle was a dealer and mechanic in Mississippi. If I'm going to pay $1600 for a saw I'm not going to go cheap on oil or gas
Echo is not the only manufacturer that recommends 89 octane or better. Stihl also recommends 89 octane as printed on the back label of their silver bottle 2 cycle oil. The addition of 2 cycle oil to gasoline actually drops the octane of fuel! Husqvarna ethanol free canned fuel actually states just that on the can. Premium grade Ethanol blended gasoline and a high quality 2 cycle oil mixed properly is all you need for your saw. Just don’t store your saw with a ethanol mixed fuel. Run it dry then put a little bit of the ethanol free canned fuel and run it to purge the ethanol out of the fuel system. Virtually all small engine equipment is vented to the atmosphere! Ethanol ( alcohol ) attracts moisture. Aviation fuel is ethanol free for a reason! Sub zero temperature at high altitude and ice in the fuel system doesn’t turn out well. Aviation fuel doesn’t atomize the same as conventional fuel either. I personally wouldn’t run it in my equipment. I’ve been told but have yet verified it that fuel sold at a marina is ethanol free fuel. Boats sit in and operate in the water! Ethanol free fuel is nearly impossible to find in my area and I can’t justify the cost. There is a reason the major saw manufacturers recommend minimum 89 octane and all ethanol free engineered fuel is 92+ fuel after blended with a Jaso FD premium 2 cycle oil
 
Echo is not the only manufacturer that recommends 89 octane or better. Stihl also recommends 89 octane as printed on the back label of their silver bottle 2 cycle oil. The addition of 2 cycle oil to gasoline actually drops the octane of fuel! Husqvarna ethanol free canned fuel actually states just that on the can. Premium grade Ethanol blended gasoline and a high quality 2 cycle oil mixed properly is all you need for your saw. Just don’t store your saw with a ethanol mixed fuel. Run it dry then put a little bit of the ethanol free canned fuel and run it to purge the ethanol out of the fuel system. Virtually all small engine equipment is vented to the atmosphere! Ethanol ( alcohol ) attracts moisture. Aviation fuel is ethanol free for a reason! Sub zero temperature at high altitude and ice in the fuel system doesn’t turn out well. Aviation fuel doesn’t atomize the same as conventional fuel either. I personally wouldn’t run it in my equipment. I’ve been told but have yet verified it that fuel sold at a marina is ethanol free fuel. Boats sit in and operate in the water! Ethanol free fuel is nearly impossible to find in my area and I can’t justify the cost. There is a reason the major saw manufacturers recommend minimum 89 octane and all ethanol free engineered fuel is 92+ fuel after blended with a Jaso FD premium 2 cycle oil
Not all two cycle oil reduces the octane rating. Some, like Honda HP2 contain components like cumene which boost octane.
The other thing to consider is that in a two cycle the only octane that counts is the octane rating of the mixture in the combustion chamber which provided the engine is up to operating twmp and running/tuned properly doesn't contain much if any oil. When pre mix enters a two cycle motor it flashes from a liquid droplet form to a vapor and deposits oil on the motors internals. The vapor then travels up to the combustion chamber where it can be combusted.
 
This thread is like a magical mystery tour of recycled old wives tales found by googling...
Exactly
First off the OP's first post can be dismissed because it's based on his manual. The same type of "manual " that probably recommends lubing needle bearing on clutch, lol which most of you say is crap. So this octane stuff printed in manuals is legal way to void warranty claims
 
Exactly

First off the OP's first post can be dismissed because it's based on his manual. The same type of "manual " that probably recommends lubing needle bearing on clutch, lol which most of you say is crap. So this octane stuff is legal crap too
Exactly correct. With the compression ratio of a saw 87 octane is adequate and loggers have worn out many saws using it with perfect results.
For instance the swept compression ratio of a stock 372xp is below 7:1. With the small bore size of a chainsaw motor 87 is more than adequate.
I still run premium for a little added insurance and because in my area it's E free.
 
Octane boosters have a very minimal effect on actual octane rating. They also have downsides like combustion deposites or degrading rubber and plastics depending on which one your using.
The first experience I had with it was a Four Winns ski boat with a 4.3 Chevy V6 . The Marina claimed to be 89 , but I doubt it. When you finished pulling somebody and shut that engine off it would diesel seems like forever. I could put a can of 104 Octane booster in a tank and it would quit just like you flipped a switch.

Same with 87 octane non ethanol that they sell in Reidsville and my 27 HP Kohler on a zero turn. When you finished mowing you would have to let it cool down for a couple of minutes or it would diesel. 104 Octane booster would stop that instantly.

Of course it is cheaper to just go find some high test than to pay for that stuff.

But, it does work as intended.
 
Exactly
First off the OP's first post can be dismissed because it's based on his manual. The same type of "manual " that probably recommends lubing needle bearing on clutch, lol which most of you say is crap. So this octane stuff is legal crap too


This pretty much explains why all the intelligent techs and operators went somewhere else.
 
The first experience I had with it was a Four Winns ski boat with a 4.3 Chevy V6 . The Marina claimed to be 89 , but I doubt it. When you finished pulling somebody and shut that engine off it would diesel seems like forever. I could put a can of 104 Octane booster in a tank and it would quit just like you flipped a switch.

Same with 87 octane non ethanol that they sell in Reidsville and my 27 HP Kohler on a zero turn. When you finished mowing you would have to let it cool down for a couple of minutes or it would diesel. 104 Octane booster would stop that instantly.

Of course it is cheaper to just go find some high test than to pay for that stuff.

But, it does work as intended.

Go piss on somebody else's leg.
Again...octane boosters increase octane very minimally.... like a few 1/10ths.
 

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