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Ok, just wondering. I am still an idiot when it comes to these engines. I hear that you should only run 93 octane in a LS1. Around here, if you get that octane you are using ethanol blended. With my ATV's, it says to NEVER use ethanol blended (not sure why, but I dont). I purchase the 110 and mix it to a 97 rated, but those are less than 5 gallon gas tanks. I do not want to have to think about the math involved to get a 93 mix, plus the inconvenience of picking up 110 and mixing it. Plus, I plan on driving around the country with my Goat. What's everyone's thoughts? :confused: Thanks!

Warren
 

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Warren said:
Ok, just wondering. I am still an idiot when it comes to these engines. I hear that you should only run 93 octane in a LS1. Around here, if you get that octane you are using ethanol blended. With my ATV's, it says to NEVER use ethanol blended (not sure why, but I dont). I purchase the 110 and mix it to a 97 rated, but those are less than 5 gallon gas tanks. I do not want to have to think about the math involved to get a 93 mix, plus the inconvenience of picking up 110 and mixing it. Plus, I plan on driving around the country with my Goat. What's everyone's thoughts? :confused: Thanks!

Warren
Like it says on the gas tank door"premium fuel recommended". You use what you have. Wouldn't worry about point or 2. We get mostly 91 here. If the engine detects detonation it pull timing out. Unless you really abuse it not likely to hurt anything, but performance and mileage will not be quite as good as with better gas. Some fuel systems have parts/ gaskets/plastics, etc that are not tolerant of alcohols so they are not recommended. Dont know about the GTO. Anybody know if they grow corn in Australia? I doubt is a problem but probably would avoid if you can. Ask the dealer. ( haha) What does it say in the book. I haven't read it yet.
 

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I've been told that ethanol attracts moisture (water) in to the fuel. This is hard on smaller engines, especially 2 strokes. I don't know if that makes sense, but it was a mechanic who told me.
 

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The ethanol can also deterioriate some of the seals in your fuel system, depending on what theyr'e made out of.

I read the owners manual and seem to remember it saying that you could run ethanol without any problems.
 

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If you use a lower octane fuel say 87-90 the knock sensors will retard the timing if they detect any knocking. This will severely affect power output. And the worse part about it is until the computer sees a change in the fuel lever it will assume the gas is still of poor quality and will keep the timing low. Performance will not return until a fresh batch of fuel is added to the tank and the computer sees a increase in fuel level.
 

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Discussion Starter #6
So I am looking at paying some big bucks for race gas, and some math to figure out the right mixture to get the 93 octane. What size of gas tank does it have (I dont have my car YET), so because of my drinking problem, I need to start on the math now.
 

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Octane rating is the fuels' ability to resist pre-ignition. The LS1 runs a relatively high (for stock) 10.25:1 compression ratio. In order to control pre-detonation/ignition and not to set off the knock sensors which in turn will retard timing (as previously mentioned), you need a fuel that will not as easily pre-ignite. I.E. 93 octane. Conversely, going with too much octane will result in poor performance just as not running a high enough octane. Usually 93/94 is more than sufficient. If and when you do heads and cam, forced induction or something else that will increase compression, then it is paramount to go with a higher octane. Going to a race fuel mixture with the stock setup won't net you anything and may actually hurt because now the fuel will even resist the spark plug trying to ignite it.

As to ethanol, due to it's attracting moisture, not only is it bad on fuel system seals, it also can corrode the pintle's in the injectors. This is a common problem on GM FWD cars and the gas commonly found to be the problem is Citgo. A bottle of Chevron Techron (GM repackages this and uses it to fix this problem) will keep this from happening or help clean the pintle's if it already is happening.

The reason they don't recommend it specifically on ATV's is because ATV's have a tendency to operate in "wet" environments which only compounds fuel system problems. I hated it when my old Polaris Scrambler would start missing in the winter do to the carb getting all corroded/gummed up on top of the moisture it was ingesting.
 

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Warren said:
So I am looking at paying some big bucks for race gas, and some math to figure out the right mixture to get the 93 octane. What size of gas tank does it have (I dont have my car YET), so because of my drinking problem, I need to start on the math now.

Certainly, using more than you need for detonation prevention is a waste of money if nothing else. LIke the research/motor methods of determining posted octane rating ( an average of the two) If you have 110 unleaded race gas with 87 octane unleaded regular (or 85 etc depending on where you are) 10 gallons of regular and about 5 (maybe 4.5) of 110 race gas will give you 93-94 .
 

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The owners manual says 91 is recommended, but no ethanol. Here in Cali the highest I can find is 91 so that will have to do. The manual also said 87-89 will work as well but accelleration may be deminished.
 

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Discussion Starter #10
The highest octane rating I can find in my small town is 91. A couple of places that have the 91, it is ethanol blended. Thanks for your imput, and good for me, the one place with the 91 is where I have an account.
 
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