Needing larger size stihl pre mix or different oil suggestions.

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Ted Jenkins
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I run a mix of 90 octane non meth fuel and 101 octane airplane fuel that has .53 percent lead in it. I’m switching from Stihl ultra mix to Lucas mix. I mix @40-1. All 6 of my saws and weed eaters run great after many years using this gas combo. I’ve got quick access to my the 101 octane Leaded gas by means of my small airport. The trace of lead in the fuel really does reduce wear….The Stihl manual says minimum octane is 89.
I find nothing wrong with leaded gas but AV gas is not engineered for the uses you describe. Why high octane when it really is not recommended. However if it does perform the way you like then do not stop. Thanks
 
Campbellcontractlogging

Campbellcontractlogging

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**** u
Red armor
I legitimately run 6 gallon of premium gas mixed 50:1 of red armor in my 592xp every week and it performs beautifully every day never have a problem I have a brand new echo 7210 that I ran 20 gallon mixed with stihl and when I pulled the muffler to mod it the piston had brown streaks down it I modded the exhaust put it together ran half tank of red armor through it pulled the muffler and the streaks where gone and a nice coating of red oil was glistening from the piston.
 

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Gone fishing
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I'm a control freak I guess, I like to know what...
I usually buy 1,3 gallon containers (5 liters) with synthetic 2-stroke oil.
I get gasoline from the gas station; 95 octane non lead.
I mix 40 to 1 (2,5%). Never had a scored cylinder.
 
bwalker
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High octane is not advised. High octane has a higher flash point. Meaning that it is harder to ignite. In a high compression racing applications then this is fine. However a chainsaw is not in this application. A lower octane rating means that the mix is easier to ignite, easier starting more power and much less cost.
None of that is true...
 
bwalker
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Especially with chain saws that do not have high compression or load a high octane fuel is not needed. Where higher elevations are concerned a very low octane is needed. Unless an OP is right at sea level where fuel is more easily ignited then using high test fuel is not practical. My point was that the higher the elevation the longer it takes for ignition to be completed in the combustion chamber. Knowing a little bit about Texas it seemed not likely a higher octane would have much benefit with few exceptions. Thanks
Fuel has the same ignition temperature regardless of octane.
 
Ted Jenkins
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Fuel has the same ignition temperature regardless of octane.
Not quite exact but I will not debate the ignition of fuel and temperature needed. And for most part most fuels will ignite relatively easy at most reasonable ignition sources. A fuel mixed with air at 10,000 feet elevation will burn noticeably slower than the same fuel at sea level. That is why advancing timing at higher elevations has benefit for most motors. Thanks
 

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Gone fishing
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Not quite exact but I will not debate the ignition of fuel and temperature needed. And for most part most fuels will ignite relatively easy at most reasonable ignition sources. A fuel mixed with air at 10,000 feet elevation will burn noticeably slower than the same fuel at sea level. That is why advancing timing at higher elevations has benefit for most motors. Thanks
But that is exact science my friend, not done with a hammer and 11 carrot fingers.
 
bwalker
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Not quite exact but I will not debate the ignition of fuel and temperature needed. And for most part most fuels will ignite relatively easy at most reasonable ignition sources. A fuel mixed with air at 10,000 feet elevation will burn noticeably slower than the same fuel at sea level. That is why advancing timing at higher elevations has benefit for most motors. Thanks
Actually it does, because octane has nothing to do at all with ignitability.
What controls how easy gasoline ignites is the RVP which basicly is a measure of how much light end components a sample has. Premium and regular have the same RVP requirements and thus the same ignitability.
 

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Gone fishing
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My 95 octane no led fuel ignites perfectly.
My 2-stroke synthetic oil does lubricate the system well, obviously.

I'm using my own built engines, your factory build engines is more difficult to get running?
 

JJT

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Feb 9, 2022
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I use premium 91 or 93 non-ethenol gas. Right now I am using dolmar/makita synthetic oil. I sed to to use stihl ultra, but it stinks and gives me a headache. At work that's what they use and when I have to do a bunch of cutting, I always stink and have a headache. It's the only oil that does that to me. I have used echo, makita, vp racing, and just ordered some amsoil Saber to try.
 

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