Octane Question
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Octane Question
So i'm and idiot and wasn't paying attention and put about 6 gals. of 89 in my truck..After I realize that i'm retarded I topped it off with like 5 gallons of 101. Question is... I had a tick over half a tank of 91, put in 6 gallons of 89, and than 5 gallons of 101..I'm running a 91 octane file..should I be concerned? or did i fix my mistake with the race gas...
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From: Botswana
Re: Octane Question
Originally posted by SICKBOY
So i'm and idiot and wasn't paying attention and put about 6 gals. of 89 in my truck..After I realize that i'm retarded I topped it off with like 5 gallons of 101. Question is... I had a tick over half a tank of 91, put in 6 gallons of 89, and than 5 gallons of 101..I'm running a 91 octane file..should I be concerned? or did i fix my mistake with the race gas...
So i'm and idiot and wasn't paying attention and put about 6 gals. of 89 in my truck..After I realize that i'm retarded I topped it off with like 5 gallons of 101. Question is... I had a tick over half a tank of 91, put in 6 gallons of 89, and than 5 gallons of 101..I'm running a 91 octane file..should I be concerned? or did i fix my mistake with the race gas...
(6x89)+(5x101)
534+505=1039
1039/11=94.45
Your good to go
Rocks
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From: Topeka Kansas
I would say your octane in the tank is over 91 now.
I assume this is in a supercharged engine and you don't want detonation and pre-ignition to occur and wreck your engine?
03LightninRocks <----- Yeah, what he said!
I assume this is in a supercharged engine and you don't want detonation and pre-ignition to occur and wreck your engine?
03LightninRocks <----- Yeah, what he said!
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From: Botswana
Glad I could help. I wish it where that easy for me to sleep. I think the older you get...the less you sleep. It must be the realization that your closer to death...so you don't want to spend the time sleeping
.....
Rocks
.....Rocks
hahaha
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From: DETROIT, (formerly Eaton County, Michigan)
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From: Chicago, Illinois
Re: Re: Octane Question
Originally posted by 03LightninRocks
(6x89)+(5x101)
534+505=1039
1039/11=94.45
(6x89)+(5x101)
534+505=1039
1039/11=94.45
You can't calculate octane ratings of mixes like that. Mixing doesn't result along a linear equation. ie: mixing equal parts of 93 and 87 actually results in something more along the lines of 89.
Still, with the nearly equal part of 101 in there, you should be close to if not over 91.
If you're worried, just stay out of WOT for a while. It usually only takes a couple of days for me to eat through a tank.
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From: Botswana
Re: Re: Re: Octane Question
Originally posted by ILLINI-SVT
NOT TRUE!
You can't calculate octane ratings of mixes like that. Mixing doesn't result along a linear equation. ie: mixing equal parts of 93 and 87 actually results in something more along the lines of 89.
Still, with the nearly equal part of 101 in there, you should be close to if not over 91.
If you're worried, just stay out of WOT for a while. It usually only takes a couple of days for me to eat through a tank.
NOT TRUE!
You can't calculate octane ratings of mixes like that. Mixing doesn't result along a linear equation. ie: mixing equal parts of 93 and 87 actually results in something more along the lines of 89.
Still, with the nearly equal part of 101 in there, you should be close to if not over 91.
If you're worried, just stay out of WOT for a while. It usually only takes a couple of days for me to eat through a tank.
Actually....it is true........The number I gave him is the number of the octane he added....not the number of the total octane of his tank.
It works like this.... One gallon of 101 + one gallon of 87 = 188/2 which equals 94.
The math is correct....trust me...LOL.
Rocks
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From: Botswana
In case ya doubt my wisdom...LOL. Here is a FAQ from the following link. http://chemistry.about.com/gi/dynami.../gasoline.html
6.15 Can I mix different octane fuel grades?
Yes, however attempts to blend in your fuel tank should be carefully planned. You should not allow the tank to become empty, and then add 50% of lower octane, followed by 50% of higher octane. The fuels may not completely mix immediately, especially if there is a density difference. You may get a slug of low octane that causes severe knock. You should refill when your tank is half full. In general the octane response will be linear for most hydrocarbon and oxygenated fuels eg 50:50 of 87 and 91 will give 89.
Check out the link...it will give you some good info on Octane ratings and how they are come by.
Rocks
6.15 Can I mix different octane fuel grades?
Yes, however attempts to blend in your fuel tank should be carefully planned. You should not allow the tank to become empty, and then add 50% of lower octane, followed by 50% of higher octane. The fuels may not completely mix immediately, especially if there is a density difference. You may get a slug of low octane that causes severe knock. You should refill when your tank is half full. In general the octane response will be linear for most hydrocarbon and oxygenated fuels eg 50:50 of 87 and 91 will give 89.
Check out the link...it will give you some good info on Octane ratings and how they are come by.
Rocks
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From: Botswana
Originally posted by SICKBOY
So what rocks was saying is I basically added the equivalent to a half a tank of 94 octane
So what rocks was saying is I basically added the equivalent to a half a tank of 94 octane
Yes....check out the link I posted above. I wouldn't stear you wrong. I am **** about my L also
Rocks
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From: Chicago, Illinois
It just goes to show, you can't believe everything you read on the internet. I'm not doubting you, as that is what I believed until I read the following:
Check it out at http://www.motorcycle.com/mo/mcrob/rt-fuel2.html
Now I'm totally lost. I actually have a friend who's a chemical engineer for an oil company, I suppose I could ask him.
Suppose I mix one gallon of 87 octane pump gas, and one gallon of 92 octane pump gas. Are you telling me that instead of two gallons of 89.5 octane gas I have something closer to 92 (like between 90 and 91)?
The mixed gas' octane rating will in general not be a linear function of the original constituents' octane ratings. Neither will it be a simple function in most cases. Rather, the octane rating becomes a quite complicated, non-linear function of some very small amounts of free radicals, such as hydroxyl and hydroxen peroxide, in the fuel. Essentially, there is no simple analytic way to predict the final octane rating of a fuel; rather, extensive tests with a calibrated engine are necessary (see MON and RON explanations in the last article).
The mixed gas' octane rating will in general not be a linear function of the original constituents' octane ratings. Neither will it be a simple function in most cases. Rather, the octane rating becomes a quite complicated, non-linear function of some very small amounts of free radicals, such as hydroxyl and hydroxen peroxide, in the fuel. Essentially, there is no simple analytic way to predict the final octane rating of a fuel; rather, extensive tests with a calibrated engine are necessary (see MON and RON explanations in the last article).
Now I'm totally lost. I actually have a friend who's a chemical engineer for an oil company, I suppose I could ask him.
