Is there a too High octane fuel?

[RyanHampton]

Faster burn is how it prevents detonation. When cylinder pressures increase you will get a detonation or a diesel effect with a slow burning or low octane rating fuel. To prevent that you must use a faster burning fuel which in effect lowers the knock rating. Higher octane fuel also requires more heat to combust. Hence why diesel is a low octane rating it has a lower combustion temperature. If you also look at how an N/A rotory works, it is better to run a low octane fuel to increase the burn time on the combustion cycle.

Thanx

[Emagdnim]

heres a good discussion on octane levels

http://www.britishcarforum.com/ubbth...=&fpart=1&vc=1

I think someone ought to sticky this thread or one of the older ones cause this question is gonna come up again.

[jboss]

Google is your freind...Be as dumb as you want and still look smart.

http://auto.howstuffworks.com/question90.htm

Higher octane only means that the fuel is more resistant to premature ignition from compression....

Fast burn, slow burn doesnt matter...The point is how much you can compress it before it explodes.

Diesel does not have an OCTANE rating....it has a CETANE rating which is a totally different thing.

It is difficult to get a gosoline over 108 octane without lead or a lead substitute.

Jet Fuel is KEROSENE-----Not 130 octane gas

[prodigy]

Originally posted by bluballz
first off, the highest UNLEADED gas i have seen is 103 octane. im assuming the 130 octane your talking about is LEADED and you will be using this in a street car with an O2 sensor. using leaded gas will f@*k up your O2 sensor.

secondly, running higher octane will NOT instantly give you more power. higher octane will only allow you to make more power safely. only if you increase cylinder pressures by either boosting more, rasing compression, advanceing timing, etc. then you will need higher octane to prevent detonation.


as stated before octane is the fuels ability resist detonation. not how fast it burns.

What are you talking about? I don't think you can even get leaded gas, key word is think here. I know you can get a lead addative for older cars that you pour in when you refuel. There are there are certain chemicals that you can put into 93 octane pump gas to bump it up to above 120 octane in your own garage.

[RyanHampton]

Lets see guys how many of you have worked in an oil refinery with chemists? I have. there is one small problem how stuff works is something you read off the internet. Yes the rate in which fuel burns is a factor in octane rating. When you use a craker tower in an oil refinery there are different chambers in which the fuel settles. Through the distilling process is how you get different grades of gas/fuel. When the fuel is compressed into the higher levels you attain a higher octane rating. At the bottom of the cracker tower chambers you get diesel oil, the next level is kerosene, then you get the lower octane fuel, then your 92, then your racing and aviation fuel levels. Now these are not complete fuels, they still have to be blended into different things. your aviation fuel has to be blended with chems that are made to run at high altitudes with low air density. That is why it is not a good idea to use it in your car contrary to popular belief. How the physics works is the same. Yes high octane gas burns faster, that does not mean more horsepower. Now did you know that adding lead to fuel increases octane rating? That is why the max unleaded fuel you can have is 110 unleaded. In order to get an octane rating of 130 it has to be leaded period. Also there has to be more things added like HRB which is a heat releasing agent that is blended with acetone. It will also have to have an another agent called nipar-6 which is another agent that is a stabilizer and mixing medium for the gas. Running this fuel in your car would not be a good idea with an O2 sensor cause it will be gone.

Thank you again.

[nissanguy_24]

Crap.. Hampton is a chemist! way to go man lol!

[RyanHampton]

Also to answer your question again. In order to advance your timing, you have to run higher octane right? Therefore the gas must burn faster to prevent knock. So yes higher octane gas does burn faster. Once again it does not increase performance. You will get the same amount of BTU out of low octane fuel. Now you can add all kinds of additives to increase performance. There are a number of oxygen bearing agents you can add to your gas to increase horsepower. One that I know of is Propylene Oxide which increases the oxygen in the cylinder therefore you can run a litlle richer. I ran this in some of my cars at about a 4% mixture and you will get about a 6% increase in power. In any concentrations higher than that you can blow the motor due to being too lean. It is also safe for O2 sensors. That is what I would use for "cheap" horsepower. Check your rules though in your class to see if oxygen bearing agents are legal. You can also add some "nitro" additives, but I'm not sure how well the medium works cause' nitro methane is not compatible with gas. The other additive is Hydrozene which is in essence rocket fuel. Hard to find, but produces big horsepower haven't seen it in a few years though.

Thanks again..

[TokiEvolution]

Wow... Your smart...

[TokiEvolution]

a kid down my block has a FC a turbo II and he went to a drag strip. i cant remember if it was 110 or 105 octane but he mix the fuel and he ran a 17.5 on the quorter mile.
I think he was pretty imbearist

[Emagdnim]

Originally posted by RyanHampton
In any concentrations higher than that you can blow the motor due to being too lean.

I just want to add why that would happen. Gas acts as a coolant to your combustion chamber before it explodes. So if you run too lean you will overheat. But most modern computer controled cars can adapt timing and fuel air mixture in order to avoid these things to a certin extent.

[Craftsman]

I'm scared of Ryan...

Someone keep him away from the books. He has knoledge in tires, chemistry, petroleum, cars, etc...

I was going to respond but Ryan kicks *Censored**Censored**Censored*.

But I second Ryan's comment about super high octane numbers being redundant...

Matt.

[PRC]

Leaded high octane race gas can also vapor lock your fuel system.

[TokiEvolution]

really??

[PRC]

yes. It has happened to a few ricer friends, who think that leaded race fuel will make their rice rockets fly higher.

[Ghost of Duluth]

Bout time Jboss came back.

Ryan Hampton, good reply.