Using O2 sensor to Adjust Carb

[Wbulk]

I recently read an article on getting accurate AF ratio readings for a carb vehicle by using an old style one wire unheated O2 sensor and reading the output with a multi-meter. You weld a sensor bung in your header, install a cheap one wire O2 sensor, and hook the positive wire on the multi-meter to the O2 sensor and the ground to body ground.

The article stated that you can accurately set the carb up with the correct main jets and determine if the power circuit is set up right. These older O2 sensors range is from 0-1 volt with an ideal cruise voltage of 400-500 mv. The power circuit should read in the 700 mv range. When I read this I thought man that makes sense. It would be a lot more accurate and faster than reading plugs and you don't need to buy one of those expensive A/F ratio monitors. You hook it up drive at a steady speed of 35-45 mph and check the voltage. Drive up a hill at a steady speed and check the voltage for the power circuit.

Has anybody tried this?

Wayne

[ItBites]

These are really only good for 'cruise' conditions. Most of our useful tuning is in transitions and at WOT (for short durations). You cannot tune accelerator pump behavior or part throttle response issues. Give it a try. I found the wideband O2 sensors to be way worth the relatively low cost and of infinitely better utility.

[SwiftDB4]

Ditto on the wideband A/Fmeter being so much better. AFX's system is about $250. Well worth it. The digital readout can be mounted for easy reading when driving, even on track days. Also if you have a Holley at least get metering blocks from Quick Fuel. That way you can at least change idle fuel jets. Better ditch the Holley for changeable air jets too.

[ack fia]

I use an A/F ratio metyer and exhaust bungs to tune my webers on the dino and in my garage. Works great for me
Pat

[Wbulk]

OK, so I've looked at the wide band systems, and there are a lot of them. I think I am partial to the Fast Racing analog gauge, 209.99 at Jeggs.