Some Info on wideband/AF mixture

[Turbo Habanero]

I was wondering how you know if you are running where you need to be with a Air flow meter. How do you know whats right for what your running ?

Not to sure on how that all works yet wondering if you guys could help me understand that a bit more.

Thanks

 

[jdub]

The Articles forum is a wealth of info
http://www.supramania.com/forums/showthread.php?t=14358

 

[Turbo Habanero]

So does this apply to all set up's ? And what exactly is wideband ? I thought it was just your ability to adjust the air fuel mixture.

A/F --- COMMENT
9.0:1 --- BLACK SMOKE (NO POWER), CYLINDER WASH
11.5:1 --- RICH BEST TORQUE @ WOT
12.2:1 --- SAFE BEST POWER @ WOT
13.3:1 --- LEAN BEST TORQUE @ WOT
14.6:1 --- STOCHIMETRIC AFR ( CHEMICALLY CORRECT )
15.5:1 --- LEAN CRUISE
16.5:1 --- BEST FUEL ECONOMY (EXCEPT FOR HONDA MOTOR COMPANY)
18.0:1 --- CARBURETED LEAN LIMIT (EXCEPT FOR HONDA MOTOR COMPANY)
22.0:1 --- EFI LEAN LIMIT

 

[jdub]

Well, you need to read and understand the whole thing

To adjust AFR on the stock ECU, you need a piggyback like the SAFC. Or, go with a full up stand alone EMS.

It's an AFR gauge...a wideband O2 is much more accurate that the stock narrow band sensor. If you want to know more than that, google it.

 

[Turbo Habanero]

Well, you need to read and understand the whole thing

To adjust AFR on the stock ECU, you need a piggyback like the SAFC. Or, go with a full up stand alone EMS.

It's an AFR gauge...a wideband O2 is much more accurate that the stock narrow band sensor. If you want to know more than that, google it.

I have been looking around so is it just a upgraded 02 sensor that will tell you your AFR?

Thanks for your help jdub

 

[TurboStreetCar]

A Wide band is exactly that, A wider band of precision.

The factory narrow band 02 sensor sends signal over a 0-1 volt range, The way it detects and outputs signal leads it to be quite imprecise to gauge AFR because its design is only to be precise to 14.7 AFR.

A factory narrow band 02 sensor simply tells the TCCS to pull or add fuel. The TCCS adds fuel untill the 02 sensor swings rich, then it pulls fuel until the 02 swings lean. It does this process relatively quickly and the end result is an average AFR of 14.7:1 by constantly pulling and adding fuel.

The TCCS doesn't look for an air fuel ratio only a voltage reading above or below the stoich threshold.

A Wide band sensor relays AFR over a 0-5 volt range. This range is MUCH more precise because the AFR's outside of 14.7 still have resolution over the voltage scale.

The more broad scale of a wide band can pinpoint AFR more precisely then the narrow band sensor can precisely detect.

I used the word precisely because both sensors are accurate as in there is a specific voltage per AFR but the resolution of the sensor is too narrow to precisely pinpoint a specific AFR.

As far as what AFR is best for your setup, the guide you posted is correct for majority of gasoline engines, Although a dyno tune by a professional is the only way to know for sure that the engine is tuned safely.

 

[Turbo Habanero]

Thankyou very much Sir :icon_bigg