Air fuel ratio 02 sensors for data

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joe 90
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Re: Air fuel ratio 02 sensors for data

Post by joe 90 » Sat Sep 16, 2017 8:31 am

Not even close.

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Re: Air fuel ratio 02 sensors for data

Post by Belgian1979 » Sat Sep 16, 2017 9:54 am

joe 90 wrote:Not even close.
Curious about your explanation. And don't forget the air vs O2 tip

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Re: Air fuel ratio 02 sensors for data

Post by Firedome8 » Sat Sep 16, 2017 4:29 pm

joe 90 wrote:
David Redszus wrote:Since the OP was with regard to O2, I'd like to pose a question.

We know that stoich means a perfect a/f ratio where all the air is combusted with all available fuel.
But a stoich a/f ratio does not produce best power; we need to go slightly richer than stoich.

Why does that work?
If we have already consumed all available air, the additional fuel does not have any air available to burn.
How can it then make more power.
It's because there's 3 different main chemical reactions happening each of which liberates different amounts of energy.
By providing an excess of fuel, you get more of the first and less of the third.

C + 1/2 o2= CO.......most energy.
CO + 1/2 o2 = CO2
H2 + 1/2 O2 = H2O.....least energy

With a lambda of 0.85 you have emissions of H2 and CO due to incomplete combustion but you shouldn't have soot.
If you go richer, you'll have soot too.
More C0 and less C02 releases more heat ?

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Re: Air fuel ratio 02 sensors for data

Post by Firedome8 » Sat Sep 16, 2017 4:33 pm

I have noticed the AFR reading lean out with added timming,,,,is the timming affecting the efficiency ????

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Re: Air fuel ratio 02 sensors for data

Post by The Radius Kid » Sat Sep 16, 2017 5:31 pm

Firedome8 wrote:I have noticed the AFR reading lean out with added timing,,,,is the timing affecting the efficiency ????
Eeyup.
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Re: Air fuel ratio 02 sensors for data

Post by digger » Sat Sep 16, 2017 5:56 pm

I always through to "consume all the air" you need to be a bit rich of stoic due to it being a non homogenous mixture

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Re: Air fuel ratio 02 sensors for data

Post by The Radius Kid » Sat Sep 16, 2017 7:06 pm

digger wrote:I always through to "consume all the air" you need to be a bit rich of stoic due to it being a non homogenous mixture
You're heading into deep water there. :shock:
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Re: Air fuel ratio 02 sensors for data

Post by joe 90 » Sat Sep 16, 2017 7:24 pm

Firedome8 wrote: More C0 and less C02 releases more heat ?
Yes.

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Re: Air fuel ratio 02 sensors for data

Post by Belgian1979 » Sun Sep 17, 2017 3:16 am

The Radius Kid wrote:
Firedome8 wrote:I have noticed the AFR reading lean out with added timing,,,,is the timing affecting the efficiency ????
Eeyup.
Hm, depends on how that added effiëncy is arrived at. I have observed that same thing. What I see at the same time is that my mafs are flowing less air, which contradicts higher effiency due to better breathing.
My reasoning here is that due to more ignition timing, the pressures in the cylinder are higher when the exhaust stroke starts, so they get out better with the charge going down the exhaust creating more of a suction effect and better cleaning out the cylinder of residual exhaust fumes which dilute the incoming mixture less.
As always the problem is how much is a good thing and when does it become negative.

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Re: Air fuel ratio 02 sensors for data

Post by The Radius Kid » Sun Sep 17, 2017 4:08 am

Belgian1979 wrote:
The Radius Kid wrote:
Firedome8 wrote:I have noticed the AFR reading lean out with added timing,,,,is the timing affecting the efficiency ????
Eeyup.
Hm, depends on how that added effiëncy is arrived at. I have observed that same thing. What I see at the same time is that my mafs are flowing less air, which contradicts higher effiency due to better breathing.
My reasoning here is that due to more ignition timing, the pressures in the cylinder are higher when the exhaust stroke starts, so they get out better with the charge going down the exhaust creating more of a suction effect and better cleaning out the cylinder of residual exhaust fumes which dilute the incoming mixture less.
As always the problem is how much is a good thing and when does it become negative.
Which efficiency are you referring to? Breathing or combustion?
The Nazis didn't lose WWII,they just changed uniforms.Now they run the place.

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Re: Air fuel ratio 02 sensors for data

Post by joe 90 » Sun Sep 17, 2017 4:13 am

Firedome8 wrote:I have noticed the AFR reading lean out with added timming,,,,is the timming affecting the efficiency ????
Change in EGT from change in timing changes the displayed AFR on the WB.


They're NOT very acccurate.

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Re: Air fuel ratio 02 sensors for data

Post by digger » Sun Sep 17, 2017 5:19 am

So how accurate are they ?

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Re: Air fuel ratio 02 sensors for data

Post by Amilcar » Sun Sep 17, 2017 9:21 am

joe 90 wrote:
Firedome8 wrote:I have noticed the AFR reading lean out with added timming,,,,is the timming affecting the efficiency ????
Change in EGT from change in timing changes the displayed AFR on the WB.


They're NOT very acccurate.
I`d be a lot more concerned with it´s accuracy, if it didn`t....

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Re: Air fuel ratio 02 sensors for data

Post by Belgian1979 » Sun Sep 17, 2017 9:45 am

The Radius Kid wrote:
Belgian1979 wrote:
The Radius Kid wrote:
Eeyup.
Hm, depends on how that added effiëncy is arrived at. I have observed that same thing. What I see at the same time is that my mafs are flowing less air, which contradicts higher effiency due to better breathing.
My reasoning here is that due to more ignition timing, the pressures in the cylinder are higher when the exhaust stroke starts, so they get out better with the charge going down the exhaust creating more of a suction effect and better cleaning out the cylinder of residual exhaust fumes which dilute the incoming mixture less.
As always the problem is how much is a good thing and when does it become negative.
Which efficiency are you referring to? Breathing or combustion?
breathing

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