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Methanol's affect on AFR readings

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Old Sep 13, 2006 | 04:16 PM
  #16  
Fourdoor's Avatar
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From: Rosedale, IN
OK, laymens terms for everyone!

An O2 sensor does NOT read your A/F ratio, it reads the O2 content of your exhaust gases.... this value is known as "lamda". To display your A/F ratio rather than the actual lamda value the wide band O2 sensor control unit does some simple calculations based on what fuel it is designed for, or in some cases what fuel the user has selected the gauge to be calibrated for.

If the control unit is set up for Gasoline, and you run E-85 (85% ethanol) the wide band would still display what would be a "normal" value for gasoline at that O2 content in the exhaust gases. If the gauge reads 11:1 at WOT you are running fat, if it reads 15:1 at WOT you are dangerously lean..... just like normal.

Keith
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Old Sep 13, 2006 | 05:10 PM
  #17  
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From: Indy
Originally Posted by Fourdoor
OK, laymens terms for everyone!

An O2 sensor does NOT read your A/F ratio, it reads the O2 content of your exhaust gases.... this value is known as "lamda". To display your A/F ratio rather than the actual lamda value the wide band O2 sensor control unit does some simple calculations based on what fuel it is designed for, or in some cases what fuel the user has selected the gauge to be calibrated for.

If the control unit is set up for Gasoline, and you run E-85 (85% ethanol) the wide band would still display what would be a "normal" value for gasoline at that O2 content in the exhaust gases. If the gauge reads 11:1 at WOT you are running fat, if it reads 15:1 at WOT you are dangerously lean..... just like normal.

Keith
I can take my Dunce-cap off now, I understand! Thanks again Keith, you don't make me feel retarted anymore!
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Old Sep 13, 2006 | 06:54 PM
  #18  
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From: houston
Originally Posted by smokedmustang
I can take my Dunce-cap off now, I understand! Thanks again Keith, you don't make me feel retarted anymore!
it's retarded, dork

just funnin with you Dr. Smoked.
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Old Sep 14, 2006 | 09:48 PM
  #19  
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From: NNJ
If you have a wideband that allows you to input the stoich value of the fuel you are using, would inputting something a little lower than 14.7 help to offset the effects of meth on your AFR. For example if I entered 14.2 would that make it so that my AFR was accurate when the meth was spraying?
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Old Sep 14, 2006 | 11:27 PM
  #20  
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From: Rosedale, IN
Originally Posted by dudical26
If you have a wideband that allows you to input the stoich value of the fuel you are using, would inputting something a little lower than 14.7 help to offset the effects of meth on your AFR. For example if I entered 14.2 would that make it so that my AFR was accurate when the meth was spraying?

For the love of GOD!!!!!!!!!

It is correct NOW. If you jack with the input, you will have to re-learn what values corrolate to rich and lean with the new value you have put in.

Yes, you can program it so that 6:1 is stoich (value for pure methonal) if you want. Do you know what A/F ratio would be way rich for meth? Do you know what A/F ratio would be dangerously lean for meth? I don't.

You could program it for E-85 (around 10:1 stoich) and once again have no clue what would be too rich or too lean.

You could program it for Pure ethonal (9:1 stoich) and (you guessed it) once again have no clue what values corrolate to too rich or too lean.

Or you can just leave it the F alone, and know that 14.7:1 is stoich, 10:1 is rich, and 13:1 is lean.

Keith
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Old Sep 25, 2006 | 02:04 AM
  #21  
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From: Kingdom of Saudi Arabia
Originally Posted by Fourdoor
Or you can just leave it the F alone, and know that 14.7:1 is stoich, 10:1 is rich, and 13:1 is lean.

Keith
lol!
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Old Sep 25, 2006 | 02:52 AM
  #22  
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From: Indy
Originally Posted by dubbleugly01
it's retarded, dork

just funnin with you Dr. Smoked.
I just saw this, always mispell that............. What is Stoich? wasn't he a kicker for the Dolphins?
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Old Sep 25, 2006 | 03:15 AM
  #23  
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From: Indy
I guess "stoich" is perfect mixture?http://en.wikipedia.org/wiki/Air_to_fuel_ratio

I am looking too deep in this I guess.
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