Running 87 octane in xp?

[atvmodster]

Can you run 87 octane in a pinch on my summit xp?I have always used 91 oct so far. Will it just hurt performance running 87 or will it be hard on engine as well?

 

[imdoo'n]

not recommended i'm sure. higher comp motor in your sled, you will burn it down if you hold throttle wide open for long. it doesn't sound like much difference going from 87 to 91 octane, but your sled will tell you when it's had enough. can be a costly tank of gas, you may save $2.00, but you may be getting a new motor.

 

[Octane]

Most places dont keep a fresh supply of premium on hand, but they do get re-supplied with regular frequently. So unless im in the mountains i run 87 - 89 just cause it hasnt been sitting for as long. and i've yet to have my sled throw a code.

 

[atvmodster]

Octane can you tell a difference in performance with 87? What is the compression of this engine? I really dont want to blow a motor. The reason i started this post was because sometimes when low on fuel its tuff to get to a premium pump. i always put in premium when at the pump thow and so far i have never put in 87.

 

[maxwell]

the summit engine runs a higher compression ratio compared to the mxz due to its design for high elevation riding. basically makes more compression to compinsate for the loss at elevation. so it is more critital to run a better fuel in a mountain sled when running at low elevation. im sure it would be fine on pump 87 but i wouldnt risk it on my machine. but to each his own. of you were riding at a high elevation it would be less of an issue.

 

[atvmodster]

ya im gunna always run 91+. two stroke engines need to be rebuilt to much as it is.

 

[DaveB]

The 800r motor is 12.25:1 compression....Summit or MXZ. 91 octane is recommended by BRP as this would be required when running at sea level. What's the elevation in St. Walburg? I would wager if you're over 2500 feet, 87 octane would work fine. My buddy runs his 800r on straight farm regular all the time. Actually, the lowest octane fuel you can run without detonation will give the best power.

 

[maxwell]

yah your right my bad. forgot we were talking about the 800r. the Ho used a differant ratio for summit and mxz.

 

[atvmodster]

i think were around 1600 feet.

 

[DaveB]

I'd stick with premium....

 

[atvmodster]

ya thats the plan.

 

[Toeknee]

For the times you can get higher octane I carry a bottle of octane boost with me.

 

[atvmodster]

I built the engine up on my old thundercat(quad) and i needed to run 91+ after. I thought using octane boosters would work for when i couldnt get to a premium pump and i found out really fast on lots of different forums and right ups that this will not work. When a bottle says it will up your octane rating 2 points this means it will go from 87 to 87.2. There is only a hand full of octane boosters out that you can use to get your reg 87 to 91. There is a company in the states that makes some and its very very pricey. People that buy all these store bought octane enhancers and use it religously are really throwing there money down the drain. I really researched these store bought octane enhancers allot.

 

[08 800 x doo]

The octane boost isn't a good idea i have been told that it does more harm than good

 

[DaveB]

Just harms your wallet. Paying big bucks for a couple oz of toluene, a couple oz o xylene, and a bit of ATF.

 

[trials rider]

i dont know a lot about octane ratings compression and jetting. but im always on the quest for knowledge.

so from what ive read on this post a higer compression motor requires the recomended octane ratings based on sea level elevation and the higher you go the lower octane you could run?

 

[atvmodster]

Yeap higher compression requires more octane. Running high octane fuel in an engine with lower compression is a waste of money. It makes me laugh when i see guys putting premium in there stock grizzly 700s and stock can-ams and they try saying they can feel an improvement in hp. Its been dyno proven that running high octane in low compression engines actually hurts horse power. Even when you put high compression pistons in a engine you want to use the lowest octane fuel possible. When i put 11:1 pistons in my thundercat (stock was 8.5:1) i found that i had better performance with 91 octane then i did with 93. For the guys that went with 12.5:1 (thundercat quad) they found 93 octane to be the best. If you use to low of octane fuel for your high compression engine you will get detonation (engine knocking). So the goal is to use the lowest octane fuel that is still safe for your engine to make peak hp. One engine that uses 12:1 compression may require different fuel then another make of engine with the same compression. Overall running premium in any sled will not hurt the motor but if its not required by manufactuar dont use it. Hope this helps.

 

[Toeknee]

I built the engine up on my old thundercat(quad) and i needed to run 91+ after. I thought using octane boosters would work for when i couldnt get to a premium pump and i found out really fast on lots of different forums and right ups that this will not work. When a bottle says it will up your octane rating 2 points this means it will go from 87 to 87.2. There is only a hand full of octane boosters out that you can use to get your reg 87 to 91. There is a company in the states that makes some and its very very pricey. People that buy all these store bought octane enhancers and use it religously are really throwing there money down the drain. I really researched these store bought octane enhancers allot.

Interesting Thanks for the info