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what grade fuel do u run

  • 87

    Votes: 385 38.3%
  • 89

    Votes: 77 7.7%
  • 91

    Votes: 329 32.7%
  • 93

    Votes: 214 21.3%

  • Total voters
    1,005
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I use 91 pump gas in both of my sidexsides and the main reason is that the higher octane fuel burns cooler and helps keep engine temps down. Since putting the turbo on the "S" I mix 50/50 110 VP with 91 pump.
run 87, my friend used to run 93 in his honda atv and kept overheating halfway through our trips...he tried some crap you put in your antifreeze called ice and it didnt help...I told him to run 87 because the lower octane helps keep the engine cooler...long story short he changed to 87 and never had an overheat issue again...
These two views are completely opposite. I guess I'll have to do some outside research on this. Just interested to know.
People with turbos and high boost often use richer mixtures and higher octane to cool things.
Wasteful, but it allows higher pressure and more power.

A lean mixture therefore runs hotter in comparison, in hard use or forced induction.
Higher octane fuels as a rule burn slower/longer, and these are nano seconds, which in turn lower octane burns (explodes) all at once, generating more heat per explosion.
Wonder why ADK's buddy was running so hot on the cooler, slower burning, higher octane fuel. Appears to be directly related to octane rating, but maybe some other factors involved.
 

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These two views are completely opposite. I guess I'll have to do some outside research on this. Just interested to know.
People with turbos and high boost often use richer mixtures and higher octane to cool things.
Wasteful, but it allows higher pressure and more power.

A lean mixture therefore runs hotter in comparison, in hard use or forced induction.
Higher octane fuels as a rule burn slower/longer, and these are nano seconds, which in turn lower octane burns (explodes) all at once, generating more heat per explosion.
Wonder why ADK's buddy was running so hot on the cooler, slower burning, higher octane fuel. Appears to be directly related to octane rating, but maybe some other factors involved.
He had a first year honda rincon and after putting on a bb kit he had overheating issues till he went to a lower octane and the overheat light never came on again. He hated putting 87 in it because he likes to use the highest octane he can find for all his machines, I go by the manual because that octane is what the motor is set up for and if I dont change anything motorwise then I feel its just a waste...prices are high enough.
 

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Fun Ride Quote
Wonder why ADK's buddy was running so hot on the cooler, slower burning, higher octane fuel. Appears to be directly related to octane rating, but maybe some other factors involved.

With out knowing more on ADK's buddy's ride I can only guess.... Oxygenated fuel can cause bike/etc to run leaner = hotter. Cleaner air filter when running hi octane = run leaner = hotter. Is it a carburetor fueled quad? Maybe bad gas? Air cooled verse water cooled. Did he ride the quad harder than usual when using higher octane,(thinking he had more power = more heat/ temp increase... the list can go on and on with out having more facts.
Rule of thumb, higher octane will not provide more power if the unit in question was designed for the lower octane. But as an engine heats up it is suppose to get richer, when it's cold it is lean, that's why you choke it.
 

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But as an engine heats up it is suppose to get richer, when it's cold it is lean, that's why you choke it.
Unless it's fuel injected, then you're not chokin' anything but yur chicken :)

Thanks, yeah not worth speculating why. Sounds like he made a bunch of mods from factory Honda setup.
 

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its all about compression boys. octane rating is a knock index. aka its resistance to knock. higher octane rating means it can withstand higher compression before it combusts due to compression which is what you hear as a ping or a knock. if your motor isnt knocking or pinging on 87, then stick with 87. you wont gain anything but a higher fuel bill otherwise. heat also contributes to pre ignition from compression. if anyone has or ever had a 90s model dodge truck with a magnum v8 engine, they know what that sounds like. when loading the engine they ping like crazy because when you load the engine you're dumping more air and fuel in. that combined with heat causes a lot of noise. if you replaced the thermostat in those trucks to a 180 from a 195 they would quit pinging. so what happens when you add a turbo? it forces more air in which means higher compression which means you need a higher octane rating. what about big bore kits? more air and fuel in the cylinders means higher compression..........isnt science fun?
 

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I run 93 in mine. Never thought about additives but I am considering it now.
 

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...I really believe with a stock 800 RZR motor you are wasting money running anything other than 87 octane, that is what it is designed to run on.
I agree!

I run Amsoil Quickshot in every tank. Full strength on the first tank, then per directions on all subsequent tanks.
 

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oldnavy
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I thought the stock compression ratio for the 09 800 is 10:1..That's why I run 91 Octane. Maybe it is overkill.

Old Navy
 

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In regards to ethanol; will the higher octane fuel last longer when sitting between rides?
 

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I always run 91 Octane since I got my RZR-S. I keep my toyhauler filled with that. I've always been told more octane makes the engine run a little cooler. With having it in the toyhauler, my generator also runs on better gas. When I'm storing the trailer or S, I always treat with Stabil.
 

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Make sure that the additive you use is made for the type of gas you are using. Stabil has a new formula for ethenol fuels vs. pure gas. I use stabil for pure gas and startron for ethenol fuels. I try to run pure gas when ever possible. I like the 10% better fuel mileage you get with pure gas compared to ethenol fuels.
 

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I run 91 due to the fact, it's what I have to run in my bike & car. It makes it easy when I fill the cans to then use it in any of my vehicles as needed.
 

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hmmm, nobody running water/meth injection? keeps the engine running cooler, cleaner, and ups the octane to 110.
 
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Higher than 87 in a engine designed for 87 is a waste.
As for additives...IF, IF you needore octane than available at the pump but don't want to run race fuel Torco Accelerator is the only true "octane booster" I've seen. It plain works for increasing the octane level, I've ran it in supercharged engines that wouldnt last seconds at pump gas octane levels with no problems. The autoparts store offerings are crap. They also claim a lower burn temp vs pump gas for a more complete burn and more power..I can't confirm that but I do put about 5 oz per tank in my XP since I have a barrel of it and I swear it runs better when I put the Torco in it. Maybe a placebo effect.
 

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Higher octane doesnt make your eng run cooler. That's a myth
Higher octane is designed to eliminate pinging. If your vehicle has this problem then you need to bump up one grade of gas. I've also been told that it does run cooler. I can find both pros and cons on the internet on this subject.
 
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