Racing/High Octane/Aviation Fuel in Chainsaws?

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I ran 87 octane in saws with well over 200 lbs of compression with no detonation problems. I did use octane booster f I remember it. A saw is turning over so fast it doesn't seem to matter about the octane as much as larger bore engines.
 
l very much respect what windthrown has to say, l really do. However in my experiance in rural areas in Ozzyland l find gas stations turn over the regular 89-91 unleaded more than they sell Premium. l have used premium a few times and can say my saws did not like it as much. l may have been imagining things but they seemed to run hotter and not start as easily. We are fortunate to get really good fuel and E10 is only found close to the city and is easily avoidable. l feel for you guys having it in almost all stations...it sucks! Fresh mix is my concern and l try to buy fuel & mix it and use within 3 days. Anything over about a week gets put in the missus little runabout (prolly good for it). Don't use stabil, nothing against it, l just find my saws like the freshest mix possible and gas that is say two weeks old is noticeably worse when starting, smoke, ect.
 
Jon did the 288 piston have any pitting on top off it? It was run with 87 the whole time I ran it?
 
Jon did the 288 piston have any pitting on top off it? It was run with 87 the whole time I ran it?
87???? You bastard! If I'd have known you ran a 230psi saw with advanced timing on 87 I never in a million years woulda bought it!!! No, it's fine.

87 octane and 93 octane gasoline both contain/produce 114,000 BTU's per gallon. Only difference is the speed of that burn. Premium burns slower, allowing further advances in timing and compression, but there is no more "energy" in premium, it does not, in and of itself, produce more power, it merely allows one to take advantage of a more highly strung engine better. I said it before, but I lied. I am now done with the "gas thread". I was gonna add a disclaimer for the earlier 100ll comment exempting Gologit. He's the real deal, and can do whatever the **** he wants. I'd be honored to cut downwind from him:bowdown:
 
That's a sign for the others that 87 is fine do saw engines. Tremonkey uses 87 also in saws with up to 250 lbs of compression also.
 
I know a lot of people that log for a living ,i do not think many of them think this hard about the fuel in their saws ,stihl mix and pump gas seems to keep them going for many years
Yah well, this is AS where we argue about anything and everything.

Also if you talk to guys that tear these engines down all the time, they tell another story. Just do a search on Lakeside Andy's posts here on AS about saws and gas and oil used in them. He has posted many times about seeing lots of detonation damage in saws running regular. He also says that any kind of dyno oil in the premix will lead to low ends gunking up.

Not exactly. Like you guys already taught me a lot of loggers tune and mod their own stuff. Plus if you are a "true logger" they probably own several saws and already lived and learned these mistakes and NOW with trail and error they know what works for them. Another reason I made this is because I need to avoid the "trail and error part".
 
If you have a method that works for your saws and you have been using it a very long time then that is what I wanted people to share with me. Because I know people around here just buy cheap gas mix the oil in with it and use the same mixture for years. I know a lot of their Stihls are 10+ years old and they start right up. I just don't think these newer saws (or anything) is made like they were in the old days. I love my MS 290 and want it to work a really long time. Even more so now that I am getting ready to pick up a MS 660. I really don't need a $1,300 purchase letting me down because of some garbage gas.
 
run the green fuel lines in the stihls ,and will not have the ethonol eating rubber problems when fuel s its in them

I'm thinking the ethanol eats Stihl fuel lines even if you don't leave fuel sitting in them. My 029S just got its fourth fuel line replacement this month, and the others have had at least two each.

I've gotten careful to run the saws dry before quitting on a daily basis, yet I'm Stihl getting fuel lines replaced every 3-4 years. The replacement lines don't seem to last as long as the originals. The dealer/shop(s) tell me "bad gas" is the culprit and sometimes try to sell me the $8 a quart fuel. I've bought some, but it's just too pricey for a real solution.

What are these "green" fuel lines, and how do i specify them if I'm taking my saw to a dealer shop?
 
I'm thinking the ethanol eats Stihl fuel lines even if you don't leave fuel sitting in them. My 029S just got its fourth fuel line replacement this month, and the others have had at least two each.

I've gotten careful to run the saws dry before quitting on a daily basis, yet I'm Stihl getting fuel lines replaced every 3-4 years. The replacement lines don't seem to last as long as the originals. The dealer/shop(s) tell me "bad gas" is the culprit and sometimes try to sell me the $8 a quart fuel. I've bought some, but it's just too pricey for a real solution.

What are these "green" fuel lines, and how do i specify them if I'm taking my saw to a dealer shop?

Doing a 15 minute repair with a $7 part every 3-4 years is a major issue? Hopefully you spend more on air and fuel filters.
 
Not a major issue, just irritating. Yeah I probably do spend more $ on filters, but filters by their nature clog, and need to be replaced or cleaned. Fuel lines could be made to last instead of being a profit center for dealers. How popular would a car be that needed new fuel lines that often?
 
Here the only avgas available is 100. Not low lead, it has a great shelf life but does corrode exhausts. At the pumps we have 91, 95 and at some stations 98 octane octane but all of them won't store well. Couple of years ago I starting selling avgas to a guy who has a lot of vintage cars and was tired of stale fuel, he eventually replaced all the fuel in those cars with avgas and says 3 years on they still start fine. Just confirmed what I knew, if you're gonna have anything sit a while avgas is the only way to go.
 
Since the only non e gas available is 93 around here, that's what I have ran for years. Hp ultra at 50.1 and no problems.
After reading this thread I might incorporate some red sta-bil to the mix to help keep the octane I'm paying for.
 
AV GAS for me. I used to have rubber issues every year and now none since switching to AV GAS. The saws run richer and with less pop. No I don't need 100 octane or lead but I love that it doesn't go bad or break down rubber. Think of all the people in LA who didn't die of lead poisoning back in the leaded gas days and heavy smog.
 
On the last trip to the airplort the pumps were down so they had me walk through the terminal to the gas truck with my cans empty and then full! I love small town airports!
 
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