So I seen a lot of talk on here about adding octane to fuel using AV Gas or Race Fuel. Back in the 90's when I was racing 2 stroke motocross, we veered away from AV Gas because of the lack of additives and inconsistencies. AV is definitely cheaper though. Now that I am installing a turbo on my sled, I want to find out what fuel to use. I see lots of sledders using AV. How about some thoughts on this?????
AV Gas vs. Race Fuel????
- Thread starter Snodawg
- Start date
100LL is all I use.
very consistent quality.
Nice blue color
Smells really good
Has to carry a minimum of 100 octane, it must be very consistently over 100 though because I've played with boost levels a lot and never had any detonation.
But I ride high elevation 8-12000ft. So there is some forgiveness that comes with elevation that high.
very consistent quality.
Nice blue color
Smells really good
Has to carry a minimum of 100 octane, it must be very consistently over 100 though because I've played with boost levels a lot and never had any detonation.
But I ride high elevation 8-12000ft. So there is some forgiveness that comes with elevation that high.
M
Couple things here:
Aviation will be the last place you will see inconsistencies, in fuels, oils, etc. that are certified. Things are kept tight regulation wise, you cant just pull to the shoulder if your engine dies.
I ran 100LL in my 850 ultra, at 185 pounds of static compression at 8300 rpm. Ran great, never had an issue untill i ran out of fuel and had to try to mix premium with other stuff, boom. Only thing i ever had to watch for was lead fouling of spark plugs.
The octane rating of 100LL is very conservative. Do a search here, there are various threads that will have some good info for you.
As far as "dryness" of the fuel, myth. Especially when youre running it in an an engine that injects oil or is premixed? LOL! If youre really worried about it, add a half cup of oil in each tankfull of gas.
Aviation will be the last place you will see inconsistencies, in fuels, oils, etc. that are certified. Things are kept tight regulation wise, you cant just pull to the shoulder if your engine dies.
I ran 100LL in my 850 ultra, at 185 pounds of static compression at 8300 rpm. Ran great, never had an issue untill i ran out of fuel and had to try to mix premium with other stuff, boom. Only thing i ever had to watch for was lead fouling of spark plugs.
The octane rating of 100LL is very conservative. Do a search here, there are various threads that will have some good info for you.
As far as "dryness" of the fuel, myth. Especially when youre running it in an an engine that injects oil or is premixed? LOL! If youre really worried about it, add a half cup of oil in each tankfull of gas.
- Oct 14, 2008
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Avgas is dry, therefore it will dry out your engine and your engine will fail.
As a matter of fact, I see airplanes falling out of the sky all the time and this is due to dry fuel.
All pilots should immediately start adding two stroke oil to their fuel tanks and lives will be saved.........Snowmobilers discovery of "add oil to your fuel" saves the aviation industry from all future crashes due to "dry" fuel seizing engines. I can see the headlines now.
Is common sense still included at birth nowadays or is it an expensive option that no one can afford at the hospital?
As a matter of fact, I see airplanes falling out of the sky all the time and this is due to dry fuel.
All pilots should immediately start adding two stroke oil to their fuel tanks and lives will be saved.........Snowmobilers discovery of "add oil to your fuel" saves the aviation industry from all future crashes due to "dry" fuel seizing engines. I can see the headlines now.
Is common sense still included at birth nowadays or is it an expensive option that no one can afford at the hospital?
Ran 50/50 av pump in my M8 last year and it definetly stopped my DET problems, and its a lot cheaper then race gas, dont think ill ever be buying race gas unless im running really high boost numbers
There are a lot more factors/properties of fuel that make it appropriate for a certain application.
How the fuel is blended and it's components can affect the character of the throttle response, detonation resistance and many other factors.
"100LL" is rated on using a different method than we are used to for motor fuels.
100LL has a motor octane rating of about 104...where 110 race fuel has a motor octane number of around 105-107.
Lots of good information on Avation fuel as it applies to sledding needs (and lots of reading) are in this thread... http://www.snowest.com/forum/showthread.php?t=220800
How the fuel is blended and it's components can affect the character of the throttle response, detonation resistance and many other factors.
"100LL" is rated on using a different method than we are used to for motor fuels.
100LL has a motor octane rating of about 104...where 110 race fuel has a motor octane number of around 105-107.
Lots of good information on Avation fuel as it applies to sledding needs (and lots of reading) are in this thread... http://www.snowest.com/forum/showthread.php?t=220800
U
Just starting to build my third turbo, and this will be my 6th year on one, in the past i have done everything from 14 psi on C12 to dropping down to see how low i can run on straight premium. Power wise i 'm betting your going to want to be somewhere in the middle like 8-10 psi. Fuel wise this is going to require you to blend fuel. premium and race gas. I don't know about you but when i try and get a 50/50 mix i eye ball a jerry can half full then i top it off with race fuel. Then i pour it in and proceed to set my box. then next tank i do the same thing only now the sled runs different. Well guess what my first mix was 45/55 and my second mix was actually 55/45. This makes a huge difference. Do yourself a favor. Run straight avgas, set your box and ride . Consistency is king
If anybody is worried about 100LL being "dry"....just throw a lil jet A in their to lube your overhead valves...
Its a math thing..... Are you kidding,you can't figure out how to calculate a 50 50 mixture????. Go to the gas station with a 5 gallon can. Turn on the pump when you see the meter show 2.5 gallons you stop. Then fill your can with race gas to the 5 gallon mark on the can. Ta da 50 50
If you mix 91 with 110 50/50 you don't magically end up with 100.5 octane...it doesn't work that way.
Y
Can't beat it in my opinion
I've run 100ll , Sunoco 110 and VP 110 all mixed 50/50 with 87 non ethanol all run fine but the VP runs the best zero detonation and crisper response. Also by far the most expensive
Is there a weight difference between 91 octane pump gas and AV gas. 5 gal of 91 seems heavier than 5 gal AV gas. Could be that I have less money in my wallet though....???
I used to do the same with 100LL.
But after experimenting with different boost levels at the elevations I ride (8-12000ft) I found that 100LL has never let me detonate and have had zero issues and excellent throttle response using the 100LL consistently at 12 psi from the 8-12,000ft range. And at 4.50 or less a gallon, why not?
I could never justify spending what most 110, 112 octane fuel costs....... Especially when trying to justify it on a millisecond of response time or a few hp or a "thought" consistency. Maybe I'm somewhat alone in this because I ride higher elevations than some do.
100LL here is fresh, underrated, easy to get, and probably more than half the price of what most guy pay to run 8psi on their sleds.
Octane alone is not the determining factor of weather or not a fuel will cause pre-ignition (detonation) in a certain application or in certain conditions for that application.
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Yes. My comment is based upon common sense, of course if someone was riding lower elevations, higher temps or higher boost or a different compression head, or different timing, or different tuning.... They obviously would have different results. There will always be plenty of variables..... And no matter what high dollar fuel you run you shouldn't automatically think you can stop taking all those factors into consideration.
U
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