Air/fuel Ratios on a NA
#1
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Air/fuel Ratios on a NA
So, I finally hooked up an O2 sensor, and decided to take a look at the readings. After letting the car warm up I took her for a spin.
I noted that most of the time my reading was .85 Volts or higher (never above .91). There was a brief time at around 3k (till about 3500 right before the secondaries kick in) I had in the .68v to .72v range.
Idle was around .85, though after hard driving an then sitting still I would see .9v for a while then it drops to the high .8v again
I have a NA, with a pretty free flowing exhaust, intake porting, TB mod, CAI and I Premix. Should I think about a SAFC II to adjust things around a bit? If I have read other threads correctly .85v represents 14.7/1 A/F ratio right? Anyway, just looking for opinions. I will be taking more readings for the next week or so to get a better feel of how the car normally operates.
I noted that most of the time my reading was .85 Volts or higher (never above .91). There was a brief time at around 3k (till about 3500 right before the secondaries kick in) I had in the .68v to .72v range.
Idle was around .85, though after hard driving an then sitting still I would see .9v for a while then it drops to the high .8v again
I have a NA, with a pretty free flowing exhaust, intake porting, TB mod, CAI and I Premix. Should I think about a SAFC II to adjust things around a bit? If I have read other threads correctly .85v represents 14.7/1 A/F ratio right? Anyway, just looking for opinions. I will be taking more readings for the next week or so to get a better feel of how the car normally operates.
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Originally Posted by pontious
If I have read other threads correctly .85v represents 14.7/1 A/F ratio right?
#3
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not really worried, just wondering. The car runs fine really. I guess I am running very rich then, from my numbers right?
And yes, on deceleration stuff drops to zero.
Do you have a set of voltage mappings to A/F ratios?
I understand the the narrow band O2 Sensor is really only good for reading values around stoic, but I should be able to tell if the car is running way too rich, or too lean.
Edit: I think I may have found an answer to my question. Does this graph look right to you?
http://hp.autometer.com/techtips/faq.../air_fuel.html
It matches up with your ~.4v number for stoic...
And yes, on deceleration stuff drops to zero.
Do you have a set of voltage mappings to A/F ratios?
I understand the the narrow band O2 Sensor is really only good for reading values around stoic, but I should be able to tell if the car is running way too rich, or too lean.
Edit: I think I may have found an answer to my question. Does this graph look right to you?
http://hp.autometer.com/techtips/faq.../air_fuel.html
It matches up with your ~.4v number for stoic...
Last edited by pontious; 01-02-05 at 11:04 PM.
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