Has anyone used an O2 sensor and Volt Meter to measure AFR (Air Fuel Ratio) to tune carb?

HWYCRZR

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So I have been thinking..... I want to make sure that my carb isn’t too rich or too lean. I could take it to a shop with an exhaust sniffer and pay $100 -$150 for them to adjust my carb air screw. But I started reading about wide band air flow sensors and gauges. Most require you to drill a hole in your exhaust pipe before the muffler and either weld in a bung or they make clamp on ones as well. I am not sure I want to do that as I am not looking for a permanent sensor installed. I am thinking about taking a sensor shielding it and putting it in the tail pipe. From what I understand you need a heated sensor.
Anybody do this?
Thanks
 
Here Is a chart I found online (everything is true on the internet)

Sure how accurate it is.
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I have not. I just use a vacuum gauge, timing light and a tach and keep twisting things till I get the highest vacuum reading I can and call it good. I'm sure others will chime in.
 
I have also used the vacuum method, but sometimes new technology is intriguing to me.
I am likely close enough with the vacuum and tach, but I want to check my work and building a tester gives me a small project to tease my brain.
 
Just get your analyzer running and hook er up.
I was looking at that. But may take a little research of which there isn’t much out there on those machines. Also from what I can tell it only measures CO (carbon monoxide) and HC (hydro carbons). Not sure how to get AFR out of those two. I was looking at the probe to see if I could put an O2 sensor on it. My first step on the analyzer is to figure out why none of meters work. Not finding much on how to bypass the control board to apply direct power to check if its the meters or the drivers/ circuit board.
 
I have used a wide band O2 sensor in my Omni Glhs turbo. I have a gauge mounted permanently in the car. Yes it is a heated sensor. It gives you piece of mind especially if the car is to loud to hear detonation. I have never used one on a carb car but ideally if dual exhaust you would want a sensor on each side. You could use one on one side I guess and read plugs too on the other side to make sure they look alike from one side to the other. 1980's used a different O2 sensor. Some were heated and some were not depending on year. Also the resolution or accuracy was fair at best. Voltage was from 0 to 1 volt and it read the 10ths of a volt for the computer to see. Wide Bands of today read from 0 to 5 volts and have better resolution and accuracy.
 
Innovative (I think) did make a setup that have a very long lead and had a stinger that would feed into the end of the exhaust, clamped. Biggest problem with that would be you have to compensate for length of exhaust, delay of guage reading.
Other way to do it would be on a chasis dyno they usually have a stinger to go up in the exhaust pipe.
 
Innovative (I think) did make a setup that have a very long lead and had a stinger that would feed into the end of the exhaust, clamped.

Yes Innovate Motorsports may make them. I use a Innovate in my car. Also check out AEM Performance Electronics too if interested.
 
I like the link @Davea Lux sent. I don’t want to permanently mount it. At least not yet. I have a single exhaust so not an issue.
The sensor in this kit is a Bosh, which is heated. I am finding that most with 3 wires are.
I like the app idea.
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I could make one of these and try it in my tail pipe. The manual says to stick the sensor in the tailpipe about 2 ft. Adjust, wait adjust. I cannot imagine that the technology in 1968 was any more sophisticated than a sensor today.
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I installed a bung in the exhaust on my Dart and adjusted the Edelbrock carb. After a couple test drives it was ready to go. The issue I had with it is that I kept watching it all the time. When I do it again, I’ll adjust, plug the bung, remove the gauge.
 
I installed a bung in the exhaust on my Dart and adjusted the Edelbrock carb. After a couple test drives it was ready to go. The issue I had with it is that I kept watching it all the time. When I do it again, I’ll adjust, plug the bung, remove the gauge.
That’s another reason for a temporary one.
 
Back in the '60s, the Sunn portable AFR meters had a sniffer tube that was placed in the end of the exhaust pipe (careful not to scoop up any of the lead deposits in the process AND had to ensure the engine was warmed up so no condensate was in the pipe). Not much lag time between the idle adjustment and when the meter changed, as I recall. That was on our '66 Newport 383 2bbl. The idle could be adjusted to the 14.2 spec, although it was not a CAP car. Taking the rpm up to 2000 or so, in "P", would yield 14.7.

The orig O2 sensors were not heated. The "heat" was needed to get the sensor up to temp sooner for closed-loop cold start emissions. The faster the sensor heated, the sooner the computer could go into closed loop. Which turbo cars needed more than the earlier carb/efi cars did, but ALL cars needed them later-on. The turbos acted like a huge heat sink for the exhaust temp during a cold start (cast iron cylinder heads and exhaust manifolds could probably be in that same "heat sink" category, too?), so the much more expensive heated sensors were needed to make things work as they needed to.

The new clamp-on bungs look pretty easy to do. Possibly replace it with a modern exhaust clamp that is a full-circle tubular design, after the tuning is done.

ColorTune was an interesting concept, but I recall thinking that you'd need to have several of them to ensure that intake manifold a/f distribution was not a factor. Like adjusting a Dearborn gas heater, you'd have to match the colors seen to what it needed to be?

I like the idea of a phone app display, especially if you could Bluetooth it.

Just some thoughts,
CBODY67
 
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