O2 sensor voltage output

[Frank F Parker]

>   I have a slip of paper circa '83 that lists O2 v relative to AFR
> Air Fuel Ratio, and one from 2-3 years ago from Cyberdyne
> who manufacturers a 10 led AFR Monitor, and the voltages
> match ie. .1v=17:1  .3v=16:  .5v=14.9  .7v=13.8:1  .9v=12.7:1

I also have a data from K&N which made a similar meter and they are all
just garbage. From Bosch graphs you can see the output in the 14.7
area is practically vertical. It is almost like a rich/lean switch.
MSD recognizes this and their meter shows just rich and lean leds on
either side of 14.7. 10 and 30 led displays are just light shows. They
can be usefull if one notes the fuel change necessary to switch.

A regular sensor is used by the GN guys with sucess because the good
guys use a dvm and tune to a specific voltage like:0.83 that has been
found from dyno/drag runs to give best times without knock etc. Without
alot of changes similar cars can also tune using that voltage.

	REAL #'s at 650 deg C
	800 mv		14.20
	700 mv		14.58
	600 mv		14.65
	500 mv		14.70
	100 mv		14.79

The 500/600/700 #'s are pretty accurate but the 100/800 #'s probably
vary alot with car/setup etc.
The 10 led meters are nothing more than a 0-1 volt meter with a led
lighting up for each 0.1 increase in voltage: 5 leds=0.5 volts.
A dvm is much better for real tuning. Note the only 0.5 a/f ratio change
for about 0.7volt change in sensor output. Please desregard any old
wives tales that say that these sensors are anything close to few .1's
change in a/f for few 0.1's in voltage- just not so!!!

Regards,

Frank Parker