Originally Posted by Chris Kemp
Chet I may be wrong but according to what I just read here
I don't think a wide band sensor would be the way to go. From what I have found it seems as though the only thing that can read the 5 wire wide band is the cars ECM. But if you have a scanner hooked to the data port it will give the readings while the car is running. What we need is an 02 sensor expert to help us figure out which type of heated sensor would be the best and how to wire it. With the little bit of research I have just done I have found out that heated sensors come in configurations of two, three and four wire. Making a devise to hold the sensor at the tail pipe would be no problem. Just a matter of welding up a six inch or so piece of pipe that would clamp to the tail pipe with an air tight fit and it would be able to place the sensor directly in the exhaust flow. No problem. I could do that easy enough. I just need to know which heated sensor to buy and how to wire it.
The "normal" O2 sensors only read a very narrow range, like 13 to 15 or something like that. Under normal conditions in a fuel injected daily driver car this is all you need. The wide band will go down into the single digits on A/F. This is what you need if tuning for performance.
I believe that thread you referenced is talking about using a wide band with a normal automotive ECM. All good standalone A/F ratio meters use a heated wide band sensor, Bosch is the most common