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on the 2004 fire cat 700 will runing 110 octane fuel make me go faster or will it shorten the life of my engine?
 

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Running any octane level higher than that recommended by the manufacturer is a waste of money. Higher octane reduces the flamability of the fuel. Its made to prevent knocking on high compression engines. It also turns over slower at gas stations so it isn't as fresh as regular. I wouldn't use it unless AC says to. But then again I have a Polaris.[:p]
 

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I don't know if it's needed for simple trail riding though. I'm sure there would be a difference, but not a big one as far as I know. If you want high octane just simple 93 would work I'd think...and most people use 87 so I guess it's up to you. If you don't race I wouldn't worry TOO much on the gas you use.
 

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Originally posted by grrandre
[br]on the new fire cat their is a swith for regular fuel or high octane.
The switch is to switch between regular gas or oxygenated(methanol/ethanol)fuel. Regular gas requires a leaner fuel map from the ECU.
 

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grrandre, the switch is for 1 purpose only

Regular fuel = 87 octane. When the switch is set to regular, it sets the timing of the engine to fire with the piston nearer TDC to prevent pre-ignition and detonation.

Premium or high octane = 92 octane. It sets the timing of the engine to fire earlier so the gas as more time to burn before the piston starts going down. What Offshore said re: octane is 100% accurate.

Running 110 without high compression heads is a waste of money.

Wannabe, reguardless of racing, you should pay attention to what gas you use, if u run 87 octane in your sled, and have the switch set to premium, there is a good chance that you will hurt your engine.
 

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That may be what the switch is for on a Polaris, but on Arctic Cat EFI the switch is for ethanol/methanol blends or straight gasoline.

It used to be a jumper wire under the hood then for '03 they gave us a switch. Now for '04 they're going back to the jumper.
 

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This brings up another question. Most people say that Premium Nox Oxy is the #1 choice for filling up sleds and other two-stokes. What are the thoughts here?
 

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I know a lot of guys who run premium fuel as a safety factor for there sleds. The old Ski-Doo HO motor requires high octane fuel. Others run it just to be sure that they don't get any detonation in the motor. The theory here would be its better to give up a couple of HP than to burn a hole in the piston.
If you are running a stock sled run what the manufacturer recommends. If you have done some mods say milled the head, ported it, Pipes, etc. You may have ro run high octane to prevent detonation.
 

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The Ski-Doo race shop recommended to us to use Amoco/BP Ultimate grade for the old 440 – pre racing fuel, 89 octane is for the other engine sizes is what I was told.
 

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I started with premium when I first started sledding but now we're on regular. Not sure I notice a difference on my sleds.
 

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I know that...but not all sleds have switches. My dad always used 89 or 91/92 on our sleds as a "precaution" I guess to prevent knock. We've never had any engine problems so I guess it's not hurting anything. He might have eased into the higher numbers, but I'm not sure. Using 87 I'm sure would be fine, but now that he's been using it I guess it COULD be bad to switch back, but I dunno. I'm not SUPER knowledgable about engines yet (I'm not retarded either but...) so I don't really know a ton about it...

But we also have silencers on all of them and run them wide open the majority of the time so....
 

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My thoughts are the added methonal / ethonal that is to replace the lead once used is a hotter burning gas. Its there to bring up the octane rating and thus more octane from methonal / ethanol is a bad thing to 2-cycle engines. We want our engines to run as cool as we can keep them and I always run 87 rating in any of my 2-cylce engines. This is my opinion only, but I have read other acticles on this backing this up. TXC
 

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Coming from a motocross background I can tell you that running race gas will improve throttle response and crispness on a stock machine....it smells niiiiccceeeee [:D] too. Not that it relates to many here but you can also keep jetting very consistent from one tank to another. Like the others said unless you're a serious racer or have higher compression don't spend the $3.50 -- $15 /gallon.

Race gas will not shorten the life of your engine. If jetted properly along with a good synthetic oil, leaded race gas will leave very few to practically no deposis. Jetted fat you'll get crap everywhere. Another misconception of race gas is it makes your engine run cooler...false. Absolutely, no way. It burns slower and longer, not cooler.
 

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Another thing that the Premium Non-Oxy provides is better shelf life. Your normal pump gas can go bad in a little time as 2 weeks. One more thing, if you use a fuel stabilizer in normal pump gas it can actually have an adverse affect on the gas and it could go bad quicker. Not so with Non-Oxy.

Once again this pertains to the crap gas found in MN and other places can be different. Most people don't know that many states call for different formulas of gas and that there is a summer and winter formula as well. I have been told over and over again that for 2 strokes, the premium Non-Oxy is the best period.
 
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