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

[HWYCRZR]

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

Just some thoughts,
CBODY67

Yes, the one above is Bluetooth. That's what intrigued me. I don't want a permanent installation.

I always relied on the old tried and true vacuum gauge with a timing light and tachometer from MAC ET-390.

Yes I am there, but I want to know how close I am to the spec. I get that way some times. And it is a new tool.

 

[Polara_500]

And it is a new tool.

And there you have it folks, no further justification required.

 

[HWYCRZR]

That is cool about $50. About $70 converted into their website.
I didn’t know there was such a thing.

Ok I admit I have a problem.
I went ahead and ordered the clear spark plug. I want to try it in a couple of cylinders to see what's happening. I saved my lunch money the last couple of weeks.
Still looking at the AFR with the O2 sensor.

 

[78Brougham]

Having the color tune kit with the one clear plug might be an advantage. This way you could compare which bank is lean or rich.
The tail pipe thing is intriguing but all 8 cyls. Are mixed up by the time you hit the tail pipe.

For example on my Lotus Elite and my MG. The front carb services cyls. 1&2 and the rear 3&4. Be neat to check them both for proper setup. I just may order one myself. The old E-Type Jags, had 3 carbs... could be a real nightmare.

 

[HWYCRZR]

Having the color tune kit with the one clear plug might be an advantage. This way you could compare which bank is lean or rich.
The tail pipe thing is intriguing but all 8 cyls. Are mixed up by the time you hit the tail pipe.

For example on my Lotus Elite and my MG. The front carb services cyls. 1&2 and the rear 3&4. Be neat to check them both for proper setup. I just may order one myself. The old E-Type Jags, had 3 carbs... could be a real nightmare.

But wait!
But I have a handy dandy engine analyser that @Polara_500 off loaded on me. None of the analog meters work on it yet, or the Co sniffer, but the oscilloscope does, and I can shut off one cylinder at a time, or either bank. (The car won't start with both banks shut off , don't ask me how I know that)
That part works. I need to read the instruction book though because it is kind of complicated.
In the end I can check the blue flame, the AFR and timing/ vacuum method and see how it all aligns. I can see it already, I am probably going to burn through a tank of gas just fiddling around.

 

[HWYCRZR]

Also for dual exhaust you can get the extra O2 sensor and harness for less than $20?

edit. I was mis-reading. Way more than $20

 

[78Brougham]

But wait!
But I have a handy dandy engine analyser that @Polara_500 off loaded on me. None of the analog meters work on it yet, or the Co sniffer, but the oscilloscope does, and I can shut off one cylinder at a time, or either bank. (The car won't start with both banks shut off , don't ask me how I know that)
That part works. I need to read the instruction book though because it is kind of complicated.
In the end I can check the blue flame, the AFR and timing/ vacuum method and see how it all aligns. I can see it already, I am probably going to burn through a tank of gas just fiddling around.

 

[Turboomni]

Also for dual exhaust you can get the extra O2 sensor and y harness for less than $20?

I believe the Bosch sensor is more than 20 bucks itself. Also I don't think you can run 2 sensors into one line into your meter. There are dual meters that have seperate systems built in. The heater circuit I would think you could run line to both but each sensor needs it's own circuit to it's own readout.

 

[HWYCRZR]

I believe the Bosch sensor is more than 20 bucks itself. Also I don't think you can run 2 sensors into one line into your meter. There are dual meters that have seperate systems built in. The heater circuit I would think you could run line to both but each sensor needs it's own circuit to it's own readout.

You are correct I was mis-reading the accessory pricing. You do need another $160 kit. I thought they had a duel module.

 

[fury fan]

I have the Innovative wideband setup on one of my cars.

Things I have learned about carbs from a WB gage:

1. You can get really good results from the old-school vacuum gage and tuneup specs (as others have said).
2. A WB on a smooth-running carb can give you AFR numbers that make you think it's a POS that needs tweaked.
3. When you put a WB gage on, you may want to fix things that you cannot. Meaning - you can't get your carb to run ideally under all conditions. You make some areas better, making other areas get worse.
4. You can see on your WB when the carb is off from ideal AFR, but you won't know which parts to change - metering rods, springs, a tweak of the idle screws? Each of those affect fueling, and can interact with each other also. A WB can't tell you what to do.
5. An engine may end up wanting AFR #s that aren't 'scientifically correct'. But you learn this only after going thru 1-5.
6. You can put a worn-out AFB from a 65 413HP on a low-CR smogger 400 and it'll run smooth as silk. Until you put a WB on it, then it's a POS. Unless you learned from 1-5 already.

 

[78Brougham]

 

[HWYCRZR]

I have the Innovative wideband setup on one of my cars.

Things I have learned about carbs from a WB gage:

1. You can get really good results from the old-school vacuum gage and tuneup specs (as others have said).
2. A WB on a smooth-running carb can give you AFR numbers that make you think it's a POS that needs tweaked.
3. When you put a WB gage on, you may want to fix things that you cannot. Meaning - you can't get your carb to run ideally under all conditions. You make some areas better, making other areas get worse.
4. You can see on your WB when the carb is off from ideal AFR, but you won't know which parts to change - metering rods, springs, a tweak of the idle screws? Each of those affect fueling, and can interact with each other also. A WB can't tell you what to do.
5. An engine may end up wanting AFR #s that aren't 'scientifically correct'. But you learn this only after going thru 1-5.
6. You can put a worn-out AFB from a 65 413HP on a low-CR smogger 400 and it'll run smooth as silk. Until you put a WB on it, then it's a POS. Unless you learned from 1-5 already.

Thanks for the feedback.
I have my original simple 2 bbl carburetor so there isn’t too much to mess with. I know me, so I know I will be chasing perfection that I might not get. My timing, dwell and RPMs are right on. My biggest challenge was figuring out my mechanical advance on my distributor was advancing around idle speed 600 rpm. I chased that for a while, but re did the advance springs this winter, now the timing doesn’t wander around. I hooked it up to my oscilloscope tonight and every thing looks even.
Timing set to 7-1/2 BTDC, 600 rpm, and dialed the idle mixture until I had about 16” of vacuum. That is about the highest it will go at 600. At around 800 rpm I am around 20”. I think it smells a little rich, but I have good throttle response with no hesitation.
Anyway here’s some oscilloscope shots.

 

[HWYCRZR]

I got my new toy today. Because of the nice snow. The mailman didn’t show up until 7:00.
I also had virtual Video happy hour from 4:30 - 6:30. So will have to wait until tomorrow to try it out.