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Fuel Octane?

For everyone running turbo kits what type of fuel (i.e VP, SUNOCO, TURBO BLUE) are you running in your sleds and also what elevations are you riding at? What octane seems to run the best or do you mix with pump gas? I have a race gas boondocker turbo kit for my 2011 hcr 800 and I was going to mix turbo blue 112 or sunoco 111 with premium fuel.
 

mk2g60

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AV gas is a joke, Never run it in a sled! Race gas kits are built for just that. I've always run VP either c-16 or a mix of c-12/c-16 in both OVS 600 & 800. I'm at 0-4000' 12-24lbs psi never had a failure from fuel, runs very consistent in all temps
 
AV gas is a joke, Never run it in a sled! Race gas kits are built for just that. I've always run VP either c-16 or a mix of c-12/c-16 in both OVS 600 & 800. I'm at 0-4000' 12-24lbs psi never had a failure from fuel, runs very consistent in all temps

What would the difference between the race fuel and the aviation fuel be? There is an airport 5 minutes from my house that sells 100ll fuel and its $4.35 a gallon. Why couldnt you run this instead of $8 plus a gallon race fuel?
 

rusty rider

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100ll is a good value for how much boost you can run. I can be at 12-13 lbs @ 10k + ft most the time. Most machines are not going to effectively run a lot more boost than 14-15 lbs due to turbo sizing anyway.
 
So what im hearing is that running 100ll fuel on a stock motor with a boondocker race gas turbo kit, I could potentially run that much pressure at any elevation? I live in Wisconsin and ride here, and also Michigan which is roughly 0-4000' and then Colorado which obviously 10000' plus. If this is true your my new best friend because this will save me a $hit ton of money instead of having to ship race fuel to my house all the time. BUT can you mix 100ll with premium in an emergency situation where i run out, have a spare 2 gallons of 100ll, and find a gas station?
 

M-Head

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You will not be able to run the same boost at 0-4000' as you can at 10,000' with any fuel. Example: you will be able to run 12 lbs of boost at 10,000' with straight av gas easily, but will severely detonate at 0-4000'.
I have been running straight av gas for years in my turbo and in my simple mind, is the best bang for the buck. I ride at 4-7000' and run 10-12 lbs boost with av gas depending on conditions. With 112 octane I would never go above 12 lbs, so why spend 5-6 dollars more per gallon?
 
So i called boondockers directly to talk about this matter because they dont respond to my emails. I think Jason had said that i could run any fuel i want. He said if you want to run anything over 10 psi of boost i will need to start running 110 octane fuel to make that type of power. He also said that i could run regular 91 premium fuel for up to 8 pounds and then should switch to 100 ll aviation fuel till 10-12 psi. I feel as though i should start out on pu,p fuel with 6 pounds of boost for my low altitude and then run the aviation fuel or race gas for when i go out west.
 

mountainhorse

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Just a heads up....talking octane numbers only.

Motor octane numbers (MON) of "race 110"

Sunoco110 and VP110....MON about 106
100LL ...................... ...MON about 103-104

HOW that fuel burns and throttle response also come into play.

The way that VP is formulated... it will, in most applications, give better throttle response than Sunoco or 100LL... Is that noticeable in a well designed turbo system on a consumers sled... depends on many things.

Big thing that I like is that 100LL does not have oxygenates in it. (no ethanol or others)

For the 10-11 lb (max) range... 100LL will give you good performance.

The old wives tales of "AV gas is dry and will ruin your seals" etc etc... you'll have to decide what is real and what is fantasy.
 
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badaltitude

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AV gas is a joke, Never run it in a sled! Race gas kits are built for just that. I've always run VP either c-16 or a mix of c-12/c-16 in both OVS 600 & 800. I'm at 0-4000' 12-24lbs psi never had a failure from fuel, runs very consistent in all temps

Lol
 
T

TheBreeze

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My real world experience of running a turbo cat in the UP, was that I had 0 issues in upper michigan running 7lbs on 100ll with stock HO head. I could have probably mixed in some pump, but why bother when 100LL is under $5 a gallon. I also ran around 9-10 psi at 100ft on 100LL. Again, maybe extra octane, but whatever. Also, you will not find elevations of 4000 ft in the U.P.

IMO you should start out with straight 100ll at 6-7 lbs around home, and turn up the boost as you increase elevation to continue to pull optimum RPM with the same clutching, and just stick to the 100ll diet. As you approach 8-9 k feet, drop a few grams out of the primary to maintain response and RPM as the air starts to get thin.
 
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WyoBoy1000

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Wtf, you guys take some stupid pills???

3 gal of 100ll with the rest 91oct is safe for 12-13lbs at 10k.
Yet running straight 100ll will make it stupid laggy and is way to much octane for peak performance.

You want to run as low of octane as possible to get the best all around performance.


In most cases on a cat you can run 6-8lbs depending on turbo size. The east way to think of it is when you exceed 170hp you need octane. But at 10k the barometric pressie drops from 15.5 @sea level to 10.2 @10k.
That means you loose 1/3rd of the air and leaves reason to believe you also lose 1/3rd of hp dropping you to about 105hp at 10k.

That's why you can run 6-8lbs safely on pg.
Yet at 5k you can only run about 3-4lbs or need a gal or 2 of rg.

On average this is a good way to consider it.
You are safe to boost like this if your baro pressure is 11.0 you can easily add 4.5lbs on 91. It basically puts you at stock power levels.
In most cases you can exceed it by 1lb on 91 Oct. After that for every 1lb of boost you need .5 gal of 100ll or higher.

So if your at 5k, the baro pressure is about 12.6.
If you want to run 12lbs you want to run about 4 gal of high octane with 91.

If by chance you hit the set sensor you drop boost .5lbs until it doest, then you know exclusive how your sled runs.

The last tm8 I had could run 6.5lbs at 10k on 91. But with 1 gal of 100ll I could run 8.5-9lbs.

But even with 2 gal 100ll running 11lbs the lag wasn't worth it. I prefer less lag.

The lower octane goes bang and gives far better low end. On the older sleds especially.
 

Iceman56

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Wyo what are you riding this year? Throw a Sidekick on and dial it all in, I wanna watch it go:face-icon-small-win
 

d1100t

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What turbo

Wtf, you guys take some stupid pills???

3 gal of 100ll with the rest 91oct is safe for 12-13lbs at 10k.
Yet running straight 100ll will make it stupid laggy and is way to much octane for peak performance.

You want to run as low of octane as possible to get the best all around performance.


In most cases on a cat you can run 6-8lbs depending on turbo size. The east way to think of it is when you exceed 170hp you need octane. But at 10k the barometric pressie drops from 15.5 @sea level to 10.2 @10k.
That means you loose 1/3rd of the air and leaves reason to believe you also lose 1/3rd of hp dropping you to about 105hp at 10k.

That's why you can run 6-8lbs safely on pg.
Yet at 5k you can only run about 3-4lbs or need a gal or 2 of rg.

On average this is a good way to consider it.
You are safe to boost like this if your baro pressure is 11.0 you can easily add 4.5lbs on 91. It basically puts you at stock power levels.
In most cases you can exceed it by 1lb on 91 Oct. After that for every 1lb of boost you need .5 gal of 100ll or higher.

So if your at 5k, the baro pressure is about 12.6.
If you want to run 12lbs you want to run about 4 gal of high octane with 91.

If by chance you hit the set sensor you drop boost .5lbs until it doest, then you know exclusive how your sled runs.

The last tm8 I had could run 6.5lbs at 10k on 91. But with 1 gal of 100ll I could run 8.5-9lbs.

But even with 2 gal 100ll running 11lbs the lag wasn't worth it. I prefer less lag.

The lower octane goes bang and gives far better low end. On the older sleds especially.

Wyoboy1000
Good info here. Thanks.
What turbo size are you refering to here?
 
C
Mar 15, 2016
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09 twisted m8. 50/50 100ll to 94. 4-8k feet. 10 lbs normally but have hit 13 and no det. Who needs boost on the trail up. Take it easy and save fuel. Once up top 12-12.2 af all day long.
 

WyoBoy1000

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Back then I ran a gt2871-2

After riding a sidekick, Boonedocker should be ashamed. Rather ride a light weight stocker.
But I'm looking at a boost it, I think Racin station has some. So far it's the only kit that has what I think it will take to make it worth it. Hopefully I'll know soon
 
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