O2 sensor reading during 1/4 mile run?
Thread Starter
Racer
Joined: Nov 2006
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From: las vegas nev
O2 sensor reading during 1/4 mile run?
i have heard you can get an idea of the A/f by looking at the o2 sensor readings on a scan tool during wo t. is this true and if so what readings a good cked this during dyno runs they were 920-945? anyone got the answer? thanx . from an old carb tuner
Intermediate
Joined: Feb 2002
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From: Homer Glen IL
Off the top of my head I would say that as long as the narrow band reading doesn't fall below the 850-860mv range you are safe but it's hard to tell your exact AFR as the narrow band resolution falls off the further you get from the 450-470 stoich switch point. Some feel you are safe at 850 and others feel you should shoot for low 900s. Without having a wide band I have tuned to the 870-930 range under WOT and feel safe until I can get a wide band unit.
Intermediate
Joined: Feb 2002
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From: Homer Glen IL
Yes 850 is leaner than 900-930 but you can't be sure what 900-930 means. It could be an AFR of 12.0 or an AFR of 13.5 so there's a lot of uncertainty at the outer limits on a narrow band. If you get an 850mv reading at WOT you may be OK and have a real AFR of 13.0 but you may have a real AFR of 14.2 which is a bit lean for max loading on the motor being pushed. Without having a wide band and running my manual thru the gears to 6200 I don't feel comfortable with a reading any lower than 870mv until I can really know the AFR using an accurate wide band.
Thread Starter
Racer
Joined: Nov 2006
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From: las vegas nev
so it sounds like i need to get a wide band sensors .what is a good unit to buy. i would want to put one in each side right . they would be a suplemen t to the o2s if I am reading you right? thanx for the help guys . OLD guy trying to learn new stuff
Le Mans Master
Joined: Sep 2000
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From: Bartlett IL
