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Discussion Starter · #1 ·
I was wondering if running my 96 polaris xcr 600 not sp monoblock with regular 87 gas would hurt it any in manual says run 89 atleast? Would octane booster help or thin my oil? I run starbrite ethanol treatment everytime and put a little oil in my gas maybe that helps. Anyways premium more or less out of my way the stores I gas up at are all regular but they get alot of traffic. Any advice would be help thanks.
 

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Torco and Lucas have been proven to be the best octane boosters, most hardly if at all raise the octane rating. You could also try toluene.

Octane boosters will be way more expensive then just buying better grade gas.
 

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Acetone in a 12:1 mix with premium gets you to 110, works on my 12.5:1cr race truck, toluene is good up to 30% concentration ( this is what most boosters are based off of), but test the mix on the rubber parts in your system to make sure it's not hard on things.
 

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regular gas won't hurt that engine at all, I honestly don't know anyone here who run premium in there's and my friend has over 10,000 miles on his. No problem
 

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Discussion Starter · #6 ·
I heard that I could from you and a couple people thats its alright, but I heard in high commpression engines you can only run 89 and up?
 

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heard the same thing with my ski-doo dealer rec 91 oct also heard if you start messin with those boosters good chance of piston problems is that true??????
 

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Don't kid yourself, that XCR engine one sweet engine and one sweet sled but it doesn't have that much compression. It might not make max hp but its something that you wouldn't even notice.

Do as you wish. This is just my experience
 

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my sled rips with some 100 octane, wont run on 87, but i do have almost 180psi per cylinder
 

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Discussion Starter · #10 ·
So what you guys are saying is 87 won't hurt it, xcrs aren't high compression? I got the monoblock high performance on the hood.
 

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That's a selling pitch, that decal. They are a little higher compression then the regular XLT but by no means does it need prem. fuel. I have never heard of octane boost taking out a piston.
 

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You only need higher octane fuel IF you have a sled with high compression. We'll get the definition of "high" in a minute. Higher octane fuel DOES NOT GIVE YOU MORE HORSEPOWER! There are no magic beans in higher octane "race" fuel. If your sled sled has high compression and you run low octane fuel, the fuel will detonate as a result of the compression in the motor as the piston approaches (but before it hits) top dead center (TDC). Your spark plug is there to detonate the fuel at that point. But if your compression is too high - the fuel will ignite on it's own due to too much pressure. This is why diesel engines do not have spark plugs - they compress the fuel to the point that it ignites on it's own. High octane fuel will not ignite on it's own under high compression. Low octane fuel will and cause either engine damage or poor performance. If your compression is around 130/135, you're probably good with 92 from the pump. Then just go up from there. It's the compression that gives you HP, not the fuel. But you must run high octane fuel in a high compression engine. The only reason the racer dudes run high octane fuel is because their motors are high compression. Running high octane fuel in a low compression engine will not hurt it, but you won't gain anything. Running low octane fuel in a high compression engine WILL hurt it.
 

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Matt331, i wouldn't say you don't gain anything from running higher octane fuel in a lower compression engine. i've found that it makes the engine run better overall. Not necessarily more power, but it runs cleaner, if that makes sense. But I do agree that you don't have to run it in a lower compression engine. I had an 04 KX250f dirtbike, and it had stage 2 hotcams, porting work, and a JE high compression piston. JE told me that at my elevation i had about 14:1 compression. So, to rais my octane, I would go to the airport and get 100LL airplane fuel and mix it with pump fuel. Never had a problem with detonation.
 

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MaineXCR said:
Ok boody thanks for the help my sled seems to run better on 91 though but I am sure they all do!
your sled runs "cooler" on 91 octane. And cooler is better. Imagine the days of the air cooled sleds. If it was 0 deg f. they run awesome. but if its 40 deg.,like crap.

Unless your engine is modded then you can run 87 with no issues if thats what your wallet can afford. Its just a XCR
 
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