rhyzin

iTrader: (1)

i dynoed 2/21/04 and also had the datalogger going for each run to see what the difference between wideband and narrowband is. here's some real numbers.

run 2 o2 comparison --->
.88 - 14.01-14.06
.90 - 13.96,13.79,13.45,13.27,13.23-13.06
.92 - 13.76,13.62,13.37,13.3,12.9,13.08,12.9,12.57,12.06-12.42
.94 - 12.0

.88 - 14.01-14.06
.90 - 13.06-13.96
.92 - 12.06-13.76
.94 - 12.0

Run 3 o2 comparison

.88 - 13.67-13.94,13.61-13.35,(13.8-12.7)
.90 - 13.5-13.41,12.97-13.31,12.64-12.44
.92 - 12.3-11.6

.88 - 13.94-13.35
.90 - 12.44-13.5
.92 - 12.44-13.5

Run 4 o2 comparison

.88 - 13.13-13.42,13.1,13.2
.90 - 12.73-12.46,12.94-13,12.39,12.79
.92 - 12.3-

.88 - 13.1-13.42
.90 - 12.39-13
.92 - 12.3-

compare

.88 - 14.01-14.06 .88 - 13.94-13.35 .88 - 13.1-13.42
.90 - 13.06-13.96 .90 - 12.44-13.5 .90 - 12.39-13
.92 - 12.06-13.76 .92 - 12.44-13.5 .92 - 12.3-

guess conversion
.88 - 13.00-14.06
.90 - 12.40-13.0
.92 - 12.06-13.4
.94 - 12.0






of course, the wideband is more accurate through all runs. the narrowband got progressively richer through each run. the thing is that i wasn't able to warm up my car before the 3 runs as they just sorta said i was up.

digdat

iTrader: (31)

for someone who is 'band-deficient', can you do a quick explanation of wideband and narrowband and the difference? I'd like to understand what I'm seeing here.

plz forgive my noobish tuning question But its much appreciated, I try and learn something new every day!

rhyzin

iTrader: (1)

no problem. i only post this stuff so people can find hard numbers and do some of their own research into things.

the basic oxygen sensor used on most factory cars are narrowband sensors. they do enough to complete the job of reporting back AF ratios and keeping the engine in safe running spec. the range this sensor reads in is from 0-1 volts where "supposedly" 0 is completely lean, about .5-.6 at stoichiometric, and 1.0 very rich.

wideband o2 sensors are much more accurate in a larger range of conditions. the range of the sensor 0-5v covering a larger range of AF ratios.

an analogy in terms of numbers, the narrowband would be like a number line that goes from 0-1 in .02 increments, and the wideband from 0-5 in .01 increments. that would sorta mean the narrowband would have 50 units of measurement in a small range of AF ratios, and the wideband would have 500 units of measurement in a larger range of of AF ratios. also, widebands have corrective circuits(i think?) that helps give better readings in a ride range of conditions whether it be environmental or whatever. this is absent in the narrowbands. in a nutshell: the wideband is VERY accurate.

so what we're looking at above is that the range of AF ratios from 11:1 - 14:1 read from the wideband lies in within .88-.94v on a narrowband. this would throw out the conventional thought that 14:1 AF on narrowband lies at .50v. it just shows here it's not true.

this might also help with general tuning with people who don't necessarily need a wideband quite yet. a wideband is recommended when going beyone basic bolt ons, and definately needed if you go to a custom turbo.

happy days.

digdat

iTrader: (31)

thx rhyzin!! i learneded me sumthin

KillahB

iTrader: (7)

Just curious as to where your value of stoichiometry was derived from.... simply because, using the O2 mod on the SAFC, my happy median point was about .7 - .8 V and at WOT it was about .98 or so V.

rhyzin

iTrader: (1)

just took values of AF for each point on the narrowband and sorta avg out a nice range. that's all the numbers up top. i was hitting around 14:1 at and between .86 and .88. i used an obd2 pda scantool to datalog.

my obd2 tool puts out different numbers than my o2 gauge. the thing though is that i made the gauge myself so it's a digital numeric readout. it gives accurate readouts on batteries, but kinda seems inaccurate when hooked up to the car. i would take the readouts from the obd2 tool over the gauge any day. it could also just be my particular o2 sensor.

HobieKopek

iTrader: (8)

Awesome. Rhyzin, you are the man.

sdhotwn

iTrader: (2)

.47 is a theoretical reference for stoichometric. It depends sensor to sensor and manufacturer to manufacturer. One of the tricks people usually have to look for is the fact that o2's can vary a bit and there can be discrepancy. I have no idea what company the .47 that people usually quote is referring to. I wouldn't be surprised if Bosch versus NGT were different stoich values. Awesome info though man, great to see this kind of real work!

Later.

Steve

HobieKopek

iTrader: (8)

It's probably Bosch. God knows they have sensors in enough production automobiles.

sdhotwn

iTrader: (2)

Bunch o info.

http://www.forparts.com/BoswidebandO2.htm

pgmike

iTrader: (27)

rhyzin, what wideband were you using adn which do you suggest to run with the greddy emanage?

lookslikeanevo

iTrader: (23)

dman mike...did you remember to dust it before you put it out ofr public view?

pgmike

iTrader: (27)

hey i respond to these where there is good info, isntead of making my own where i will get dumb responses

lookslikeanevo

iTrader: (23)

^ya ture....hey at least you used the search buttom..lol this thing must have been burried in there

pgmike

iTrader: (27)

actually it was the ONLY one that came up bc nobody deals with this kidn of stuff with teh reg lancers