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Air Fuel Ratio Sensor/Monitor

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Trick6

Trick6

Jedi Hopeful
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I just installed a AFR sensor bung and looking around at sensor/monitors. I am interested in the Wideband sensor/monitor setup. I don't mind if it is in kit form. Any users out there with recommendations?
 
There's some talk of that in this thread, and some more here.

I opted for a narrow band setup. Cost was a big consideration. I use the OE O2 sensor in my supercharged Miata with a Westach analog gauge. It gives me enough info in that environment, so I thought I'd try it for the TR3.

Edit: I'm glad to see so much interest in modern techniques for tuning these old carbureted cars. If done properly, the results should be much better then lifting pistons at idle to set the mixture. I want to know what's happening throughout the whole engine range under all conditions.
 
Al, one problem with what you are asking is that you will have 3 TBI and you would need a sensor for each. Unless you have isolated the Headers correctly it would put the O2 's real close to the head.

This is the way i see it,but I'm just a novice. Please set me straight because I am A Tim the Tool Man follower.

<span style="font-size: 26pt">MORE POWER!!!</span>
 
Thansk Art:
I saw this thread and the photo. I asked Paul (BROSKY) what O2 unit he is using, but no reply. So I am asking for recommendations and or references.
 
Oh, Al has electronic fuel injection. That's no fair! :hammer:
 
Don:
I am not sure about the need for a sensor for each TBI. However, my header is a 6-3-1. The firing order from 6 pipes to 3 pair of pipes does not collect in pairs by carb body. In other words, I cannot do three sensors, one for each carb, as you foresee. I have placed the bung in the collector very close to the merging of the three down pipes.
 
Art:
I do not have EFI yet. It is coming. Rick Patton has been figuring on the conversion. Three TBI's present a problem. Odd number of injectors vs. firing order. That kinda thing. But Rick says that it will be done.
 
How can you tell if all the TBI's are correct?That was my pondering
 
Paul, it was on another post. There are about 3 currently running with about the same info
 
Don:
When I first installed the tri carb set up the read out was very rich. VERY RICH. The plugs were (sooty) not that bad as far as reading but the dyno registered 11.5 AFR at 3000 RPM and it went down to 11.0 at 3500 and flattened out there to 5500 RPM. I tried to make the adjustment while on the dyno but there was no improvement. The carbs came with the wrong needles. I got the BIAF's and installed them and the car responded brightly. I have not retuned to the dyno yet because of other upgrades being made but the plugs went from sooty to just barely gray. The motor responds now with the slightest adjustments of needle height settings. It put out 118 HP at the rear wheels running very rich (11.0). With that as a base, this little motor is going to improve 10-15% HP with the correct mixture.

Hope this info helps.
 
I see that on carbs but on a TBI can you do the same ?
Have a TBI on my van, but don't know much about it and I am real interested in building a new head with them
 
I have the B1AF's in mine and my mixture seems to be fine, but I did have to play with it a bit after the installation o fthe meter. Prior to the NGK Meter, I didn't know how rich I was running at WOT until the dyno runs last summer.
 
Don:
Once you have the TBI, the fuel setting is greatly simplified. There are no needle adjustments to make. The carbs are just air doors (throttle bodies). You can tune with the laptop. The motor will perform at optimum fuel metering which will improve the gas mileage and performance. Here is Rick Patton's explanation. https://www.pattonmachine.com/ConversionBenefits.htm
 
Trick6 said:
https://www.alamomotorsports.com/knn/knn_afr.html (Don't know if this one is a wideband)
Click to expand...
Pretty sure it's not. K&N's photo shows only one wire to the sensor.
https://www.knfilters.com/airfuelmonitors.htm

Not sure who to believe ... the wide-band folk claim the narrow-band sensors are only accurate at exactly stoichiometric; and both widely variable and highly non-linear away from that point. Supposedly even the stoich point varies with temperature and pressure; neither one of which are very constant in an exhaust system. But monitors based on narrow band sensors are all over the place, and they never talk about accuracy ...
 
What are you looking for it to do? A dashboard gauge is one thing, a data logger is another.

Myself, I've got the LM1 system from Innovate, with the tailpipe adapter. That way I can use it on any vehicle, read the display while I drive if I wish, and datalog what was going on.

If you're really interested in low buck and kits, there was a good thread on the GRMS board about a 9 months ago. You can get kits for a dashboard type display for under $100.
 
foxtrapper:
I have looked at the Innovate LM1 and like it. I don't need the gauge mounted in the car so I am looking at a tuning tool and data logging with computer assistance. This looks like the one to have. Thanks.
 
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