Air Fuel Ratio
06-29-2006, 01:22 PM
#41
Originally Posted by 02sierraz71_5.3
I understand that Im not challenging what your saying about stoich afr. What I am challenging is the use of the word "perfect" as the definition explicity states
"Completely suited for a particular purpose or situation" Blown chevy made a statement that 14.7 is the perfect afr, if he simply ment that its stoich duck a dur this is obvious. I thought that he was stating that its the best afr to run and his statement was so blanketed it left room for discussion which is what Im doing.
Im discussing different AFR ranges and thier inherent benefits. Egos arent in the way its point counter point thats what a discussion is.
"Completely suited for a particular purpose or situation" Blown chevy made a statement that 14.7 is the perfect afr, if he simply ment that its stoich duck a dur this is obvious. I thought that he was stating that its the best afr to run and his statement was so blanketed it left room for discussion which is what Im doing.
Im discussing different AFR ranges and thier inherent benefits. Egos arent in the way its point counter point thats what a discussion is.
The word perfect was based on the Stoich theroy. Again, I dont think you understand the basis of the thread......
06-29-2006, 01:25 PM
#42
Originally Posted by 02sierraz71_5.3
I understand that Im not challenging what your saying about stoich afr. What I am challenging is the use of the word "perfect" as the definition explicity states
"Completely suited for a particular purpose or situation" Blown chevy made a statement that 14.7 is the perfect afr, if he simply ment that its stoich duck a dur this is obvious. I thought that he was stating that its the best afr to run and his statement was so blanketed it left room for discussion which is what Im doing.
Im discussing different AFR ranges and thier inherent benefits. Egos arent in the way its point counter point thats what a discussion is.
"Completely suited for a particular purpose or situation" Blown chevy made a statement that 14.7 is the perfect afr, if he simply ment that its stoich duck a dur this is obvious. I thought that he was stating that its the best afr to run and his statement was so blanketed it left room for discussion which is what Im doing.
Im discussing different AFR ranges and thier inherent benefits. Egos arent in the way its point counter point thats what a discussion is.
Though, in a perfect world/engine/scenario, you would see no performance benefit whatsover from running richer than 14.7, it would be just a waste of fuel and a slight power decrease as the cooler burn would result in a lower pressure.
06-29-2006, 02:38 PM
#43
TECH Addict
- BACK ON TOPIC -
At what point does a mixture run TOO RICH in relation to what it should be....I mean, we all know that 10:1 AFR will start to wash cylinder walls down, but at what point does it become too rich to be safe ???
At what point does a mixture run TOO RICH in relation to what it should be....I mean, we all know that 10:1 AFR will start to wash cylinder walls down, but at what point does it become too rich to be safe ???
06-29-2006, 02:45 PM
#44
Originally Posted by Yelo
- BACK ON TOPIC -
At what point does a mixture run TOO RICH in relation to what it should be....I mean, we all know that 10:1 AFR will start to wash cylinder walls down, but at what point does it become too rich to be safe ???
At what point does a mixture run TOO RICH in relation to what it should be....I mean, we all know that 10:1 AFR will start to wash cylinder walls down, but at what point does it become too rich to be safe ???
06-29-2006, 02:55 PM
#45
Originally Posted by Yelo
- BACK ON TOPIC -
At what point does a mixture run TOO RICH in relation to what it should be....I mean, we all know that 10:1 AFR will start to wash cylinder walls down, but at what point does it become too rich to be safe ???
At what point does a mixture run TOO RICH in relation to what it should be....I mean, we all know that 10:1 AFR will start to wash cylinder walls down, but at what point does it become too rich to be safe ???
However, doing a little reading on the explosive limit of gasoline, it has a upper and lower limit.
http://en.wikipedia.org/wiki/Explosive_limits
I thought the octane rating would affect this, you'd think at least. But with this knowledge, we can conclude (guess, at least me
) that 10.5:1 is a bad scenario. (Gasoline's Lower Explosive Limit is 1.4%. 14.7/1.4 is 10.5) I just made that up, LOL sound alright for speculative? Souds good to me, stay away from 10.5:1 with gasoline!
06-29-2006, 02:57 PM
#46
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Originally Posted by dc_justin
English language is a crazy animal.
Though, in a perfect world/engine/scenario, you would see no performance benefit whatsover from running richer than 14.7, it would be just a waste of fuel and a slight power decrease as the cooler burn would result in a lower pressure.
Though, in a perfect world/engine/scenario, you would see no performance benefit whatsover from running richer than 14.7, it would be just a waste of fuel and a slight power decrease as the cooler burn would result in a lower pressure.
why we are discussing since every one agree that in a "perfect world" 14.7 means 100% fuel burned?
it's better to discuss what is the best AFR for any application.
06-29-2006, 03:01 PM
#47
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Originally Posted by bomariam1
this the seconde time that I send this thread (I don't know why it wasn't entered?), any ways.
why we are discussing since every one agree that in a "perfect world" 14.7 means 100% fuel burned?
it's better to discuss what is the best AFR for any application.
why we are discussing since every one agree that in a "perfect world" 14.7 means 100% fuel burned?
it's better to discuss what is the best AFR for any application.
06-29-2006, 03:06 PM
#48
I was thinking about ethanol, looking at that chart its LEL is 3%!!! I guess that ruins my hypothesis for a formula... 14.7/3=4.9! LOL
I think I got it backwards.
***Yeh backwards,
So, this mean when the air/fuel mixture is 7.6% of fuel, it becomes unignitable? Hence washdown?
I think I got it backwards.
***Yeh backwards,
There are two explosive limits for any gas or vapor, the lower explosive limit (LEL) and the upper explosive limit (UEL). At concentrations in air below the LEL there is not enough fuel to continue an explosion; at concentrations above the UEL the fuel has displaced so much air that there is not enough oxygen to begin a reaction. Concentrations of explosive gases are often given in terms of percent of lower explosive limit (%LEL).
06-29-2006, 03:10 PM
#49
Originally Posted by dewmanshu
I was thinking about ethanol, looking at that chart its LEL is 3%!!! I guess that ruins my hypothesis for a formula... 14.7/3=4.9! LOL
I think I got it backwards.
I think I got it backwards.
I'd think that 3% would be 3% of volume as the limit... 100% / 3% = 33.3:1
Same with Gasoline
Rich Limit: 100/7.6 = 13.1:1 Lean Limit: 100/1.4 = 71:1
Compression has a big effect on these numbers as well, I'm just not certain how much.
06-29-2006, 03:11 PM
#50
Originally Posted by dc_justin
Yeah, the units aren't exactly right for that.
I'd think that 3% would be 3% of volume as the limit... 100% / 3% = 33.3:1
Same with Gasoline
Rich Limit: 100/7.6 = 13.1:1 Lean Limit: 100/1.4 = 71:1
Compression has a big effect on these numbers as well, I'm just not certain how much.
I'd think that 3% would be 3% of volume as the limit... 100% / 3% = 33.3:1
Same with Gasoline
Rich Limit: 100/7.6 = 13.1:1 Lean Limit: 100/1.4 = 71:1
Compression has a big effect on these numbers as well, I'm just not certain how much.