school boy

what is the differences between the wideband labeled air/fuel ratio gauges and the non labeled ones? what would you reconmend running in my car? im running a o/r x pipe and the oxygen sensors will be turned off and used for the a/f ratio gauge.

cliffyk

What do you mean by "...wideband labeled air/fuel ratio gauges and the non labeled ones."?

Taking a guess at what you are asking, a gauge that's intended to be used with a wideband sensor system require that you have a wideband controller and a wideband sensor, the gauge connects to the WB controller's output--not the sensor. An exception, I believe, is that AEM and perhaps others, makes a WB gauge with a built-in controller.

Gauges intended to be used with a narrowband sensor just require that they be connected directly to the NB sensor's output--and are generally worthless for tuning a modern EFI system...

school boy

yea im pretty new and worthless when it comes to a/f ratio gauges! lol! but you answered my question perfectly. how come the narrow bands worthless?

AirBrontosaurus

Narrowband sensors can only tell you if your mixture is richer or leaner than 14.7:1 (stoichiometric). They can't tell you how much richer or how much leaner, which is very important to know when tuning.

Wideband setups tell you exactly what the mixture is. So say your mixture is 13:1; the wideband will read "13:1" on the gauge, whereas the narrowband will simply say "RICH". You can see how much more useful the wideband is for tuning than the narrowband.

If you're just trying to tune for idle then a narrowband is OK, but your computer already does all the idle and part throttle tuning for you. It doesn't need your help, unless you do some major modifications to the engine.

What you yourself need to tune is the WOT fueling, which the narrowbands have no effect on (in fact, they're basically turned off when at WOT). Plus, you want your WOT fueling to be in the 11:1-12:1 area, but all the narrowbands are good for is 14.7:1. So you would have no way of knowing how accurate your fueling is up top, because all you would ever see is "RICH" (or "LEAN" if you're doing something incredibly wrong), which isn't too helpful when you're trying to dial in a specific ratio.

school boy

i understand what you're saying. thanks for the help. im trying to get all the understanding i can for when i start going bigger, hopefully this spring+ i have the sniper delta force and want to 'play around' with it so to speak and see if i cant get any bigger #s. thanks again, its been a big help

vanquish

If you already have Delta Force definately get a wideband.

school boy

yea, got the special forces and the delta force with 2 bullitts( basicly unused!) for 400 shipped!

Hangwire

Not to thread hi-jack but....I have a question about what sensor a wideband set-up uses.

First off, i'm under the impression that a wideband setup uses an 02 sensor JUST like the one you have in your midpipe already. Given this you can technically just use that 02 sensor to supply information to your wideband. But if you do this, can the same 02 sensor still do its original job? Doesnt seem like it would work that way.

So if you consider all of this if you wanted your 02 sensor to continue doing its current job AND have a wideband setup you would need to tap another sensor into your midpipe? Fill me in!

school boy

make that 2 of us fill in

AirBrontosaurus

Good question. The stock O2s in the back of your exhaust are narrowband because of the voltage they output. Their output function looks kind of like this:



That means that at anything even slightly RICH, they are maxxed out at full voltage. Similarly, the signal cannot tell you how LEAN the mixture is, because once it goes outside of its range it simply reports very low voltage.

So, if your AF reading is outside of their useful range (in this case, 14.1:1 to about 15:1) then the sensor only reports one value. Since that value is the same for ALL lean AF ratios, you cannot discern what actual AF ratio that value corresponds to, and as such you can only know if it is RICH or LEAN.

A wideband sensor outputs different voltages for each AF (it's actually more complicated than that, but for all intents and purposes that's what it does). It looks like this:



It is then possible to take that output voltage, normalize it using some mathematical function, and turn it into a usable AF signal. Since the voltage differs for ALL possible AF ratios, any voltage reading is equivalent to a different AF mixture (within reason).

The narrowband O2 meters in your exhaust are far more accurate than the wideband sensor, which is why they can be used for fine tuning. However, the wideband sensor can cover a much larger span of AF ratios, which is why you need it to dial in tuning when you don't specifically want a 14.7:1 ratio (for instance, at WOT).

Most wideband sensors CAN be configured to output a narrowband signal to your computer. However, a narrowband sensor CANNOT be configured to output a wideband reading. It's just not in their design.

To directly answer your question: A narrowband sensor CANNOT output a wideband signal, thus the narrowband sensors in your midpipe CANNOT be used as a wideband. You need a special wideband sensor to get the actual wideband AF data.