You get the most power out of the lowest octane that you can run. On new saws thats 89 if u go by manual. But in my area I buy pure no E gas in premium and the lack of ethanol is worth the trade off in some miniscule power loss. And the reason u get less power is that octane is resistance to burn causing a slower burn that is not as instantaneous, so you dont have as harsh of an explosion and or you lose some out of the exhaust possibly as fuel is not completely burned before exhaust port is exposed. Simple explanation from a simple backyard mechanic not a builder.
Really MM , so your one of those running 87 in our new saws ? I did notice that the manual on that 011 I got that it says to uae regular 87 cause premium has something that damages gaskets or something ? But that saw is like 25 yrs old and fuel is not even the same now.
So I should run 87? I panicked one time and poured the 87 into my car at the gas station and refilled the can with 89 when I wasn't paying attention.
I have run 87 by accident. Do what you want. Personally I dont think it will matter. But stihl says 89 , BUT they also say 50:1
I've run 87 all summer long in some ported saws with 200 lbs of compression. The ignition is so quick at 11k rpms the 93 isn't going to do anything but be slower burning. I've not noticed any thing to tell me I need to up the octane.
I have run 87 and premium (93 around here) in my new saws and it did not make one bit of difference that I could detect. The saws don't need it, and the notion that premium is better fuel just because of the higher octane rating is hogwash. Some companies blend their high grade differently, (remember Mobil and 'drive your engine clean?') and in some areas premium is available as ethanol free. That changes the game a bit. You should run whatever you are comfortable running unless given a compelling reason to do otherwise.
Yep thats what I said too run what you feel comfortable with. For me I run premium because I get it ethanol free. Any small amount of power loss is worth it to mr to not worry as much about water absorbtion and deteriorating rubber as well as fuel going bad faster than pure fuel. The last is not as big an issue cause the oil I have run has a stabilizer added.
I run 87 since its the freshest normally. I have run 93 sometimes just because but I didn't notice a change in tuning. Now race gas you will notice it running richer.
Yea had not even thought of that ? I know e10 has less but than regular of same grade. I mention it all the time when talking cars , not sure why did not think of it here ? I can get regular real 87 too now that I think of it. I get it for the boats and at. Maybe...?
