What is the big difference and where do you get avgas at? Which one is better, pros and cons and why?
avgas or racegas?
- Thread starter mkhoskins
- Start date
The Ogden airport has AV gas and they will sell it to you. I was looking the other day and it was around $4 or so. I like to run race gas but that is just my preference. I have ran av gas before and with your setup it would work fine. You may have to tweak the numbers some but it would work. I will have to ask what a drum of race costs this year. You could probably mix in 3-4 gallons of race in each tank and be more then safe with your setup. The race I have always ran is sunoco 112. GOOD STUFF.
M
modsledr
Well-known member
100LL av gas is the equivalent of 102-105 octane auto fuel (different octane rating system).
Some will claim it is a "dry" fuel and that is somehow bad...Av Gas has a very low moisture content (to prevent from freezing at altitude).
Av Gas has anti-detonation additives for boosted applications (large % of supercharged engines in planes).
Av Gas has a pretty high lead contect which will foul up your O2 sensor.
Av Gas is very high quality and will last longer in storage without degrading.
All of this info is available online...do a little research of your own for your own peace of mind.
Some will claim it is a "dry" fuel and that is somehow bad...Av Gas has a very low moisture content (to prevent from freezing at altitude).
Av Gas has anti-detonation additives for boosted applications (large % of supercharged engines in planes).
Av Gas has a pretty high lead contect which will foul up your O2 sensor.
Av Gas is very high quality and will last longer in storage without degrading.
All of this info is available online...do a little research of your own for your own peace of mind.
i thought a guy with a turbo already would know this answer?!?
S
sled-fiend
Well-known member
J
johnny be bad
Well-known member
ive ran av gas for yrs. as has many of my friends. weve had zero problems. works fine. if your worried about being dry? add a little mix oil.
T
TRUEBLUEMAX
Well-known member
Ran with a guy last year with a rx1 running around 20 lbs. of boost. He was running av gas. He liked it better than race fuel. He was getting his down at the refinery in North Salt Lake. That may be closer to you depending on which was you go to ride in the winter.
nope
no, just got the turbo, been a two stroke mod guy forever... thats why I am asking
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Scott1
Active member
I read some where that av gas has a different specific gravity than race gas, I also remember something about the av gas being formulated for a low constant rpm at super high elevation, I will try to find the info and post it, I run 50/50 race/premium with the supercharger on my sled, but I've run av gas in my 450 with no problems.
Av Gas has very different properties...
I've been diving into this lately too since the pump fuel sux so bad for quality and consistency.
AV Gas has less energy in it (measured in BTU/lb)... AV, about 18,700 BTU/lb, Race gas is about 19,000 for C10... 20,000 for C12
Av Gas has different distillation numbers... the temp at which the fuel vaporizes...AV Gas is MUCH higher in this temp range... which can handicap the throttle response. This higher Vap temp (set at 275°F by FAA specs) keeps the pistons cooler... but they are not interested in any kind of throttle response issues with an airplane... Planes just dont "snap, snap, snap" the throttles like power-sports do. They run at a constant speed and generally not nearly the RPM of a sled motor.
110 VP and 110 Sunoco ("standard") are 107 and 105 MON octane respectively.
Conoco-Phillips did a standard MON test of their 100LL AV gas recently... and it came out as 104 MON.
Lots of people use and swear by AV Gas... but I have to wonder how they are comparing the performance... For me.. It would have to the same conditions, using the same sled with the different gas (drained), same rider.
For a direct replacement for 91 pump fuel... in something that would normally run 91... I don't think 100LL is anywhere near the ideal fuel.
For the high boost strictly hillclimbers that are not relying on the transitional throttle response... That would typically burn 110 Race Gas (105-107 MON) ...The AV Gas at 104 MON might just be the ticket for this WFO type of operation... it would also keep the pistons a bit more cool.
I've been diving into this lately too since the pump fuel sux so bad for quality and consistency.
AV Gas has less energy in it (measured in BTU/lb)... AV, about 18,700 BTU/lb, Race gas is about 19,000 for C10... 20,000 for C12
Av Gas has different distillation numbers... the temp at which the fuel vaporizes...AV Gas is MUCH higher in this temp range... which can handicap the throttle response. This higher Vap temp (set at 275°F by FAA specs) keeps the pistons cooler... but they are not interested in any kind of throttle response issues with an airplane... Planes just dont "snap, snap, snap" the throttles like power-sports do. They run at a constant speed and generally not nearly the RPM of a sled motor.
110 VP and 110 Sunoco ("standard") are 107 and 105 MON octane respectively.
Conoco-Phillips did a standard MON test of their 100LL AV gas recently... and it came out as 104 MON.
Lots of people use and swear by AV Gas... but I have to wonder how they are comparing the performance... For me.. It would have to the same conditions, using the same sled with the different gas (drained), same rider.
For a direct replacement for 91 pump fuel... in something that would normally run 91... I don't think 100LL is anywhere near the ideal fuel.
For the high boost strictly hillclimbers that are not relying on the transitional throttle response... That would typically burn 110 Race Gas (105-107 MON) ...The AV Gas at 104 MON might just be the ticket for this WFO type of operation... it would also keep the pistons a bit more cool.
R
RKT
Well-known member
MH... all good stuff and true.... I think with the problems today of pump gas (not knowing what you are getting) I think it may be wise for all 91 octane people to add about 2-3 gallons of AVGAS to a tank just to be safe... As for using it as a sub for 114 race gas.. many do it.. but there are some tradeoffs... but they may or may not be that apparent..
In any case, the pump fuel today is always suspect, especially if it is blended with Ethanol.. so, the Avgas....is an easy effective method of increasing the octane..
too bad the government is trying to hit us at the heart of our recreation high performance by targeting our fuel source...
That is pretty interesting to know the MON octane numbers...especially since 110 was almost twice the cost of AV gas last winter, yet only 1 octane higher on the MON rating. I can live with a little less snap if it is going to save me a few hundred dollars.
I toasted a boosted rx-1 on avgas. Doing 660' speed runs at 10 pounds boost at 1400' elevation.....not pretty!!! Clutching & A/F was dead nutz on!!!!
E
EZmoney
Well-known member
How is it you are certain it was the fuel?Besides the fact of clutching and a/f being bang on that day? Just asking? You could have had detonation weeks before or months while you were tunning? So many things could have caused ya damage and let go that day while making a run.Ever hear of the odd race car throw a rod out the block while warming it up? Ya it has happend. I know i had no issues along with several others i know.I ran my old BD turbo on my apex with just a head shim for a couple years on av gas and the motor was perfect when i opened it up last year.Maybe i just got lucky or maybe you just had some bad luck. Besides the fact im really board...
cheers
Av Gas actually runs cooler than Race gas... at 10 lbs.. it wasn't av gas issues IMO...something else was wrong most likely.
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avgas 15lbs (apex) has been good here for the last couple of yrs.
avgas so easy to find up here and cheap. of course if u want to run more, high octane is a good choice
avgas so easy to find up here and cheap. of course if u want to run more, high octane is a good choice
E
endeavorslc
New member
Torco Fuel Concentrate!
Just wanted to through out TORCO. I have one full season on my SC Nytro at 12lbs boost with super unleaded and and the corresponding TORCO additive to equal 102 octane. It only adds about a dollar a gallon and out performs 50/50 racemix which is more like 95 octane. One of the best things about it is you could be in the middle of nowhere and run out of gas. So if you rely on avgas or race fuel your out of luck for hundreds of miles. Magically you pull a 16oz container out of your pack and add it to any unleaded fuel and you will make it back to your trailer safe and sound with out worry of damaging your engine. Peace of mind is priceless!
http://torcoracefuel.net/pro-accelerator.html
http://torcoracefuel.net/2-docs/accelerator-blend-chart.gif
Just wanted to through out TORCO. I have one full season on my SC Nytro at 12lbs boost with super unleaded and and the corresponding TORCO additive to equal 102 octane. It only adds about a dollar a gallon and out performs 50/50 racemix which is more like 95 octane. One of the best things about it is you could be in the middle of nowhere and run out of gas. So if you rely on avgas or race fuel your out of luck for hundreds of miles. Magically you pull a 16oz container out of your pack and add it to any unleaded fuel and you will make it back to your trailer safe and sound with out worry of damaging your engine. Peace of mind is priceless!
http://torcoracefuel.net/pro-accelerator.html
http://torcoracefuel.net/2-docs/accelerator-blend-chart.gif
T
Thunderguy BOOSTED
Well-known member
just a random one...... what is the MAX HP you would want to run on strait AV??
W
wpnyturbo
Member
last winter i ran 16psi on a stand alone impulse set up on my 2010 nytro all on straight avgas and it ran flawlessly at 3to 6 thousand feet but i don't think i will be turning it up any higher unless on race gas because of elevation here in alaska it was 3.88 a gallon so not much different than premium.
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Thunderguy BOOSTED
Well-known member
ok lets say in a RX1 stage 2 rear Mount MCX??? MAX BOOST???
