What is considered the "perfect AFR" ???
05-02-2002, 07:46 PM
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What is considered the "perfect AFR" ??? What would be the "perfect Air Fuel Ratio" ? I'm trying to decide if a MAFT would do me any good. I'll wait until I get a few answers before I say what my #'s are. <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
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05-02-2002, 07:57 PM
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Re: What is considered the "perfect AFR" ??? This would be a great topic for the tuning section <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Good luck Jay! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Good luck Jay! <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
05-02-2002, 08:05 PM
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Re: What is considered the "perfect AFR" ??? Ideal A/F ratio is 12.8:1 (12.8 to 1), (stiametric?, spelling?). <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
05-02-2002, 08:18 PM
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Re: What is considered the "perfect AFR" ??? mine is at 12.5 - 12.6 would a MAFT really help or am I close enough as it is? I though 12.5 was ideal or so I had been told that a while back, thats why I was seeking a second opinion.
05-02-2002, 08:26 PM
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Re: What is considered the "perfect AFR" ??? Ideal AFR is like ideal timing, ideal shiftpoints, etc. - it doesn't exist as a single value.
Each vehicle will work best at a certain a/f ratio, but it will not be the same for all of them.
Additionally, your a/f ratio at max power will vary vs. rpm - you will be the richest at peak torque, and leanest at max rpm.
Load itself will also effect a/f ratio - readings ona dynojet will be richer than on the street/track.
You might try starting out around 12.6-12.8:1 at the torque peak and leaning out to 13:1 at the hp peak, but trial and error with quantitative feedback is the only way to get it perfectly setup.
(this is assuming a na car - a FI car will be probably half a point richer at least)
Chris
Each vehicle will work best at a certain a/f ratio, but it will not be the same for all of them.
Additionally, your a/f ratio at max power will vary vs. rpm - you will be the richest at peak torque, and leanest at max rpm.
Load itself will also effect a/f ratio - readings ona dynojet will be richer than on the street/track.
You might try starting out around 12.6-12.8:1 at the torque peak and leaning out to 13:1 at the hp peak, but trial and error with quantitative feedback is the only way to get it perfectly setup.
(this is assuming a na car - a FI car will be probably half a point richer at least)
Chris
05-02-2002, 11:32 PM
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Re: What is considered the "perfect AFR" ??? Chris, nothing personal, but I do disagree. having had a lot of time on engine dyno's, (not chassis dyno's) and over 25 years drag racing experience with Chevy's, 12.8 to 1 is the optimum. Even warren Johnson shoots for that over the entire spectrum of powerband. Powerband is the key word here. But getting exactly that ratio ALL the time is impossible. Aim for the bulls eye
(12.8) and you'll be fine. 13 to 1, slightly leaner, but close. Don't take my word for it though, ask companies like Holley, Edelbrock, Barry Grant, Braswell, etc.
Cheers. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
(12.8) and you'll be fine. 13 to 1, slightly leaner, but close. Don't take my word for it though, ask companies like Holley, Edelbrock, Barry Grant, Braswell, etc.
Cheers. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
05-03-2002, 01:18 AM
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Re: What is considered the "perfect AFR" ??? So according to you a certain a/f ratio is required regardless of the conditions of the cylinder (pressure, temp, etc?)
You are claiming that at peak torque, where cylinder pressure, etc. is at it's highest, you will need the same ratio as you will 300rpm past your hp peak where you are hitting a big cylinder filling wall?
Also, all that aside, it *IS* impossible to make such a broad generalization. A/F ratio is going to be a result of the amount of fuel to air - it gives no indication of it's atomization, charge quality, etc.
A 2 barrel rochester carb on a 24" runner intake will not make the best power at NEAR the same a/f ratio as a dry 10" runner fuel injectoed intake, or a dominator on a 3" tunnel ram, etc. - all will effect the actual atomization.
Air fuel ratio itself is not the final factor - it is modified by charge quality as mentioned above (which is primarily a factor of atomization and the positioning of the kernel in the combustion chamber). So again, it's impossible for there to be an ideal "ratio".
All that theory aside just get on a dyno with a wideband. Try it yourself and you will see what is going on.
Also, as another point, the fact that Warren Johnson supposedly shoots for a certain a/f ratio is irrelevant - the setups are not the same - he also does quote a few other things that aren't applicable to a streetable car. Also FWIW his fuel has a different stoichiometric ratio than ours, so the comparison is moot anyway. And I challenge you to actually find reputable material that backs up the claim - somehoe I don't think warren johnson is going to be giving up his secrets <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Chris Bennight
You are claiming that at peak torque, where cylinder pressure, etc. is at it's highest, you will need the same ratio as you will 300rpm past your hp peak where you are hitting a big cylinder filling wall?
Also, all that aside, it *IS* impossible to make such a broad generalization. A/F ratio is going to be a result of the amount of fuel to air - it gives no indication of it's atomization, charge quality, etc.
A 2 barrel rochester carb on a 24" runner intake will not make the best power at NEAR the same a/f ratio as a dry 10" runner fuel injectoed intake, or a dominator on a 3" tunnel ram, etc. - all will effect the actual atomization.
Air fuel ratio itself is not the final factor - it is modified by charge quality as mentioned above (which is primarily a factor of atomization and the positioning of the kernel in the combustion chamber). So again, it's impossible for there to be an ideal "ratio".
All that theory aside just get on a dyno with a wideband. Try it yourself and you will see what is going on.
Also, as another point, the fact that Warren Johnson supposedly shoots for a certain a/f ratio is irrelevant - the setups are not the same - he also does quote a few other things that aren't applicable to a streetable car. Also FWIW his fuel has a different stoichiometric ratio than ours, so the comparison is moot anyway. And I challenge you to actually find reputable material that backs up the claim - somehoe I don't think warren johnson is going to be giving up his secrets <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Chris Bennight
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05-03-2002, 06:18 AM
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Re: What is considered the "perfect AFR" ??? After much wideband usage on different cars, I have to agree with Chris. Because of differences in engines, even the same type of engine from vehicle to vehicle, you can't put a value to the PERFECT AFR. On many turbo cars, high 11s is the desired AFR. Others swear they can run very fast on a lean 13:1 AFR provided there is no detonation. On most cars running a wideband, they are taking an average of several cylinders, so you have to take into account that every cylinder may not be the same (regarding airflow). On an LS1 this is minimized (hopefully). So if you have one cylinder running 12.0:1 and another running 13.0:1, you'll see 12.5:1 on the wideband 02. Start leaning that motor out, and you may find that lean cylinder start detonating. I guarantee you will lose power (maybe a piston too).
Brian Green
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05-03-2002, 01:36 PM
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Re: What is considered the "perfect AFR" ??? Wow! We are in a LS1 Tech area and someone is talking about a 2 barrel carb on a 24 inch runner intake. Ever hear of not seeing the forest because of the trees?
When you say "perfect" ratio, do you mean perfect for horspower, for emissions, or for fuel economy? I don't think you will find one number for all on the same engine, but I could be wrong.
When you say "perfect" ratio, do you mean perfect for horspower, for emissions, or for fuel economy? I don't think you will find one number for all on the same engine, but I could be wrong.
05-03-2002, 03:41 PM
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Re: What is considered the "perfect AFR" ??? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Vettepartz:
<strong>Wow! We are in a LS1 Tech area and someone is talking about a 2 barrel carb on a 24 inch runner intake. Ever hear of not seeing the forest because of the trees?
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ever hear of someones point going about 200 yards over anothers head?
<strong>Wow! We are in a LS1 Tech area and someone is talking about a 2 barrel carb on a 24 inch runner intake. Ever hear of not seeing the forest because of the trees?
</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Ever hear of someones point going about 200 yards over anothers head?
05-03-2002, 04:45 PM
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Re: What is considered the "perfect AFR" ??? I'm thinking the question was asked so the little people like me would have a ball park number to shoot for. Hell if we knew all of the stuff that is talked about in this threat the question would not have been asked. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
05-03-2002, 10:08 PM
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Re: What is considered the "perfect AFR" ??? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by ChrisB:
<strong>Ideal AFR is like ideal timing, ideal shiftpoints, etc. - it doesn't exist as a single value.
To quote from 'Racing The Small Block Chevy', authors include Chuck Gulledge (for those who don't know him, Fuel induction expert and ex-Holley engineer, nice guy to deal with, Smokey Yunick, Robert Yates, John Reed, Harvey Crane), "Since an engine performs best at one air/fuel ratio" (Page 109), disagree with these guys??
Each vehicle will work best at a certain a/f ratio, but it will not be the same for all of them.
True ChrisB, I agree, however, what is it your after?? Absolute power, economy or least emissions?? Since this thread was begun with a question by someone wanting to know, presumably about A/F ratio for best power, then that is 12.8 to 1. Leaner, such as 13.5 and higher, is for economy, etc. Specific exotic fuels (Methanol, Ethonal, etc) are totally different.
Additionally, your a/f ratio at max power will vary vs. rpm - you will be the richest at peak torque, and leanest at max rpm.
Load itself will also effect a/f ratio - readings ona dynojet will be richer than on the street/track.
I agree also ChrisB, that due to varying loading, and other factors, the A/F ratio will change itself in the combustion chamber. HOWEVER, that was not what was asked, he asked the ideal A/F ratio. (Nearly) anyone knows that in the real world, the A/F ratio will change, but ideal is not real world, BUT is what we need to shoot for (Read: Tune towards).
Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">That's my 0.02c worth (May cost up to 0.04c in Australia)....
<strong>Ideal AFR is like ideal timing, ideal shiftpoints, etc. - it doesn't exist as a single value.
To quote from 'Racing The Small Block Chevy', authors include Chuck Gulledge (for those who don't know him, Fuel induction expert and ex-Holley engineer, nice guy to deal with, Smokey Yunick, Robert Yates, John Reed, Harvey Crane), "Since an engine performs best at one air/fuel ratio" (Page 109), disagree with these guys??
Each vehicle will work best at a certain a/f ratio, but it will not be the same for all of them.
True ChrisB, I agree, however, what is it your after?? Absolute power, economy or least emissions?? Since this thread was begun with a question by someone wanting to know, presumably about A/F ratio for best power, then that is 12.8 to 1. Leaner, such as 13.5 and higher, is for economy, etc. Specific exotic fuels (Methanol, Ethonal, etc) are totally different.
Additionally, your a/f ratio at max power will vary vs. rpm - you will be the richest at peak torque, and leanest at max rpm.
Load itself will also effect a/f ratio - readings ona dynojet will be richer than on the street/track.
I agree also ChrisB, that due to varying loading, and other factors, the A/F ratio will change itself in the combustion chamber. HOWEVER, that was not what was asked, he asked the ideal A/F ratio. (Nearly) anyone knows that in the real world, the A/F ratio will change, but ideal is not real world, BUT is what we need to shoot for (Read: Tune towards).
Chris</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">That's my 0.02c worth (May cost up to 0.04c in Australia)....
05-03-2002, 11:19 PM
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Re: What is considered the "perfect AFR" ??? I posted a reccomendation above also.. yep
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">You might try starting out around 12.6-12.8:1 at the torque peak and leaning out to 13:1 at the hp peak, but trial and error with quantitative feedback is the only way to get it perfectly setup.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
The point is don't shoot for an air fuel artio and call it quits there - it is a good tool to get you close to ideal, but in the end I would use more direct resutls - dyno then track.
Chris
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">You might try starting out around 12.6-12.8:1 at the torque peak and leaning out to 13:1 at the hp peak, but trial and error with quantitative feedback is the only way to get it perfectly setup.</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
The point is don't shoot for an air fuel artio and call it quits there - it is a good tool to get you close to ideal, but in the end I would use more direct resutls - dyno then track.
Chris
05-04-2002, 12:12 AM
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Re: What is considered the "perfect AFR" ??? ChrisB,
I agree with that idea of dyno first, then track, been doing that since 1978.....BUT LS1JAY who started this thread probably knows that too. However, he wanted an ideal A/F ratio.... He got it IMHO.....
Cheers
PS, I'm up anyyytime for a challenge, love them...!
I don't proclaim to know everything, only some things from experience, others I search for (such as this site <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" /> ) and engine dynoing/drag strip time...If I can help someone, then I will!
Peace <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
I agree with that idea of dyno first, then track, been doing that since 1978.....BUT LS1JAY who started this thread probably knows that too. However, he wanted an ideal A/F ratio.... He got it IMHO.....
Cheers
PS, I'm up anyyytime for a challenge, love them...!
I don't proclaim to know everything, only some things from experience, others I search for (such as this site <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" /> ) and engine dynoing/drag strip time...If I can help someone, then I will!
Peace <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
05-04-2002, 01:55 AM
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Re: What is considered the "perfect AFR" ??? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Will Race 4 Food:
<strong>To quote from 'Racing The Small Block Chevy', authors include Chuck Gulledge (for those who don't know him, Fuel induction expert and ex-Holley engineer, nice guy to deal with, Smokey Yunick, Robert Yates, John Reed, Harvey Crane), "Since an engine performs best at one air/fuel ratio" (Page 109), disagree with these guys??</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif"></strong>
I guess that proves that people aren't perfect, everyone makes mistakes, etc. You can quote other people all you want, I am more curious as to how you answer the above concerns I raised within the context of one ideal A/F ratio.
Do you really believe if I took 2 identical engines, and put a 24" intake and a 2 barrel carb on one, and a 3" tunnel ram with a dominator on the other they will both make the most power at the same a/f ratio? If so how do you account for the atomization of the charges, etc. being so different, yet supposedly needing the same fuel flow.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">True ChrisB, I agree, however, what is it your after?? Absolute power, economy or least emissions?? Since this thread was begun with a question by someone wanting to know, presumably about A/F ratio for best power, then that is 12.8 to 1. Leaner, such as 13.5 and higher, is for economy, etc. Specific exotic fuels (Methanol, Ethonal, etc) are totally different. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Power of course, I don't think anyone except you mentioned anything else. Again, you claim 12.8:1 is the perfect ratio, but you still haven't backed it up (and no, the quote doesn't count - please answer some of the concerns I have brought up)
Again, why is 12.8:1 the magic number?
Chris
<strong>To quote from 'Racing The Small Block Chevy', authors include Chuck Gulledge (for those who don't know him, Fuel induction expert and ex-Holley engineer, nice guy to deal with, Smokey Yunick, Robert Yates, John Reed, Harvey Crane), "Since an engine performs best at one air/fuel ratio" (Page 109), disagree with these guys??</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif"></strong>
I guess that proves that people aren't perfect, everyone makes mistakes, etc. You can quote other people all you want, I am more curious as to how you answer the above concerns I raised within the context of one ideal A/F ratio.
Do you really believe if I took 2 identical engines, and put a 24" intake and a 2 barrel carb on one, and a 3" tunnel ram with a dominator on the other they will both make the most power at the same a/f ratio? If so how do you account for the atomization of the charges, etc. being so different, yet supposedly needing the same fuel flow.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">True ChrisB, I agree, however, what is it your after?? Absolute power, economy or least emissions?? Since this thread was begun with a question by someone wanting to know, presumably about A/F ratio for best power, then that is 12.8 to 1. Leaner, such as 13.5 and higher, is for economy, etc. Specific exotic fuels (Methanol, Ethonal, etc) are totally different. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Power of course, I don't think anyone except you mentioned anything else. Again, you claim 12.8:1 is the perfect ratio, but you still haven't backed it up (and no, the quote doesn't count - please answer some of the concerns I have brought up)
Again, why is 12.8:1 the magic number?
Chris
05-04-2002, 02:12 AM
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Re: What is considered the "perfect AFR" ??? ChrisB,
"VettePartz" asked about something other than power. Please read his reply before making statements.....Why 12.8 to 1??
For the fuel we are talking here, being being gasoline with a specific gravity rating of 0.680 to 0.750, (and a MOTOR octane of 93 or better, however octane in A/F ratio does NOT matter, as octane suppresses detonation only), 12.8 to 1 is THE ideal ratio. (With Methanol, 7 to 1 is ideal, but thats another story..)Who says 12.8 to 1??
W.J. for one. Bill Jenkins, Smokey Yunick, Chuck Gulledge, I can keep listing them if you want...
I could find specific articles by these pioneers, but too time consuming for me through my library...If you don't believe me or them, I won't lose any sleep over it....
Also in your reply you quoted 'fuel flow' on two different engines... We are NOT talking about fuel flow in this thread, but rather A/F ratio in the chamber of said engine when the valves are closed and piston is on compression stroke on a four cycle engine with a specific gravity of 0.680 to 0.750. (Octane has little to do with fuel energy, but specific gravity has EVERYTHING to do with fuel energy).
Cheers <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
<small>[ May 04, 2002, 02:41 AM: Message edited by: Will Race 4 Food ]</small>
"VettePartz" asked about something other than power. Please read his reply before making statements.....Why 12.8 to 1??
For the fuel we are talking here, being being gasoline with a specific gravity rating of 0.680 to 0.750, (and a MOTOR octane of 93 or better, however octane in A/F ratio does NOT matter, as octane suppresses detonation only), 12.8 to 1 is THE ideal ratio. (With Methanol, 7 to 1 is ideal, but thats another story..)Who says 12.8 to 1??
W.J. for one. Bill Jenkins, Smokey Yunick, Chuck Gulledge, I can keep listing them if you want...
I could find specific articles by these pioneers, but too time consuming for me through my library...If you don't believe me or them, I won't lose any sleep over it....
Also in your reply you quoted 'fuel flow' on two different engines... We are NOT talking about fuel flow in this thread, but rather A/F ratio in the chamber of said engine when the valves are closed and piston is on compression stroke on a four cycle engine with a specific gravity of 0.680 to 0.750. (Octane has little to do with fuel energy, but specific gravity has EVERYTHING to do with fuel energy).
Cheers <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
<small>[ May 04, 2002, 02:41 AM: Message edited by: Will Race 4 Food ]</small>
05-04-2002, 03:23 AM
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Re: What is considered the "perfect AFR" ??? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Will Race 4 Food:
12.8 to 1 is THE ideal ratio. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Again, WHY? You can drop plenty of names, but you still haven't addressed the issues of atomization/charge quality?
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
I could find specific articles by these pioneers, but too time consuming for me through my library...If you don't believe me or them, I won't lose any sleep over it....
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
So your stance is "this is what I believe, I am not going to take the time to prove it though I promise you I can"
?
<img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
but rather A/F ratio in the chamber of said engine when the valves are closed and piston is on compression stroke on a four cycle engine
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Okay, so you are talking about the a/f ratio in the cylinder. Fine. Now are you claiming atomization has no effect on power output?
What if I take 2 12.8:1 mixtures - one is a lump of fuel - the other is perfectly atomized. It's pretty obvious which one will make more power.
But we of course never have perfect atomization.
The intake path/fuel injector/carbureation, etc. will all effect atomization.
So what you are claiming is that at *any* atomization level 12.8:1 will make the most power? Am I getting this right? And does that *really* make sense to you?
Again, please give me some sort of qualitative or quatitative reasoning for the 12.8:1 value, or if it's experimentally determined please provide some evidence.
If you are going to make a point it's not really constructive to simply state your opinion and claim it's not worth your time to back it up - if you wish to make claims you need to supply some sort of logic/supporting evidence, etc.
Finally have you ever actually had your car on a dyno with a wideband - can you honestly claim you have *never* *ever* made more power at any point with an a/f ratio other than 12.8:1? Have you ever actually tried? Try it, I think you will be suprised.
Chris
12.8 to 1 is THE ideal ratio. </font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Again, WHY? You can drop plenty of names, but you still haven't addressed the issues of atomization/charge quality?
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
I could find specific articles by these pioneers, but too time consuming for me through my library...If you don't believe me or them, I won't lose any sleep over it....
</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
So your stance is "this is what I believe, I am not going to take the time to prove it though I promise you I can"
?
<img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">
but rather A/F ratio in the chamber of said engine when the valves are closed and piston is on compression stroke on a four cycle engine
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Okay, so you are talking about the a/f ratio in the cylinder. Fine. Now are you claiming atomization has no effect on power output?
What if I take 2 12.8:1 mixtures - one is a lump of fuel - the other is perfectly atomized. It's pretty obvious which one will make more power.
But we of course never have perfect atomization.
The intake path/fuel injector/carbureation, etc. will all effect atomization.
So what you are claiming is that at *any* atomization level 12.8:1 will make the most power? Am I getting this right? And does that *really* make sense to you?
Again, please give me some sort of qualitative or quatitative reasoning for the 12.8:1 value, or if it's experimentally determined please provide some evidence.
If you are going to make a point it's not really constructive to simply state your opinion and claim it's not worth your time to back it up - if you wish to make claims you need to supply some sort of logic/supporting evidence, etc.
Finally have you ever actually had your car on a dyno with a wideband - can you honestly claim you have *never* *ever* made more power at any point with an a/f ratio other than 12.8:1? Have you ever actually tried? Try it, I think you will be suprised.
Chris
05-04-2002, 07:09 AM
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Re: What is considered the "perfect AFR" ??? Sorry guys, I didn't mean to start a war! <img border="0" alt="[fight]" title="" src="graemlins/gr_punch.gif" />
