Wideband O2 sensor for tuning

[redgum78]

Looks like there are several kits out there that can be used.
Example;
http://www.ebay.com.au/itm/like/152464383187?chn=ps
Has anyone played with this sort of thing?
Particularly interested how useful it was for jetting and tuning.

I am also very interested if anyone has made their own unit.
Obversely a wideband O2 sensor would be purchased. From there is it as simple as supplying it with the correct voltage (seems 5v is common) and then reading the output on a meter that is configured for the correct range?
From what I read some wideband O2 sensors output 0v to +5v and others output a positive or negative current flow in mA with zero current flow equalling stoich.

At this point I can't see why a regulated supply of the appropriate voltage to the probe and a multi meter in V or mA depending on the probe to read the output would not work?
Some are saying a controller device is required? Does the probe need a variable reference voltage/current that comes from a controller?

[Calif240]

I've got an O2 sensor plugged up in mine. The bung is mounted at the end of my long-tube header, just after the pipes come together. It is nice just to keep an eye on things and peace of mind. It is helpful if you're doing lots of changes to things, but once you get your carb set, it shouldn't require much change to jetting, etc. I like mine and it was purchased through Summit Racing for about $200. Don't go cheap, I've heard bad things about the cheap ones.
Terry

[justcruisin]

Some do need a interface between the sender and the gauge, others like the MTX gauge in your link are inbuilt, as to what the difference is I am not sure, I think it is something to do with adding on other equipment if desired but unless you are gyro gear loose you might as well buy the kit, besides - the gauge gives you a number in A/F that you can see instantly, if your going to use a volt meter I can't say that would be as good. I guess if that's your thing it could be fun to build your own. What I can say is that the MTX is a great tool, I have had one in my car for 5 years with zero issues, I have friends using the same gauge with the same results. As far as a stand alone gauge goes the MTX is a good choice and well worth the money, especially if you are on the edge of detonation. The drag strip is also a very useful tuning tool for full power runs - unless you have the money for dyno time. For $ spent it is one of the best tuning devices you can add to your car IMHO.
When tuning you do need to record a run, not a good idea to try and look at the gauge with your foot up it, that"s where the outputs come in handy, I'm a bit of a cheap bastard so i just set up a camera in front of the gauge together with rpm and vacuum.

[Troy]

I have an NTK version. I did a lot of research before I picked it over the Innovate but that was a couple years ago.
https://www.amazon.com/NTK-AFRM-GEN2-Monitor-Wideband/dp/B018GX1AO2

I used it to tune the Six Pack on my 440 that I could never get to run right and it was awesome! Haven't had to pull a spark plug to look at colors yet... I bought a pile of extra bungs (with caps) so I can move it from car to car. I hang the gauge thingy above my sun visor so I can monitor things while driving and without rigging up a mount.

With a carb you can only tune so much. You can get it perfect for a specific day but then the next day it's 20 degrees colder with high humidity and you're futzing with it again. So, use the wide band to find a happy medium. You don't tune for perfect ratio (14.7 I believe) as that will end up being too lean more often than not. I think my Six Pack is usually idling near 13 and when I mash the pedal it goes into the 11s momentarily then back to the high 12s while accelerating. Upon decel it may jump to something like 17.

The NTK has a 12v power and a ground wire that goes into the controller. I run mine straight off the battery but I disconnect the battery whenever the car is parked. Otherwise, it will stay on forever and burn out the sensor. You could run it off a switched power if you wanted. The controller sends the proper voltage to the sensor and handles all the conversion from resistance to an actual number. Mine has a 5 volt analog output signal to run a gauge off of for permanent mounting.

My O2 sensor has 5 wires. I think the ones on my Toyota trucks (the only other thing I mess with at this level) are 2 wire - but they are NOT wide band and only give a thumbs up/down value. If you knew the output range of the sensor then you could figure out the "scale" for the air/fuel reading. Really, a good wide band O2 sensor is over $100 and I don't have a lot of free time so buying one with a gauge (and the complete wiring harness) makes a lot more sense. If I were permanently installing them in each car, I might try to find a cheaper solution.

Troy

[XH29N0G]

I am a fan.  Bought an innovate unit and also use a laptop to log it.  As noted, the readings change with gas and season.  It was extremely useful for solving some issues with my carburetor.  I get the sense that getting the carb dialed in, however, depends on the track and experience.  I also learned a whole lot.  I can now can set it up for whatever A/F I want, but the key now is knowing whether it is something like 13.2, 12.8, 12.5 ....?

When I was looking people said they set up ones without the kits, so it can be done.  I think it was Cooter who did that, but haven't seen him online in a long time.  My son said he could easily set up a logger using something like an Arduino, but I have not taken him up on it and am not knowledgable enough to do myself.

I recommend it, but it won't kill you not to have it.

[68CoronetRT]

Fitech comes with an AFR sensor/bung and for a couple hundred bucks more you can have FI....  

[redgum78]

Thanks guys for the feedback. This was exactly what I was looking for.

I have picked up an Aussie Charger (A body) with a 400 stoker and six pack carb set up shoe horned into it. The guy never drove it with the 6 pack so I am not confident that it is tuned correct. I want to run it down the strip but need to at least get it jetted close so I don't lean out and melt stuff!

I was also thinking of fitting a bung and plug to my other cars just to see where they were at and fine tune if the system was accurate enough. If I could get a DIY version down to $100-$200au I would permanently fit one to all my cars. Plus I like messing with electronics and such.

Thanks for all your feedback. I think the Innovate MTX kit will do the job just fine by the sounds of things. Once I have that sorted I might mess with a home made rig and compare the 2 side by side.

[68pplcharger]

https://www.summitracing.com/parts/atm-3370

I like my gauges matching and yes they are great for tuning the carb. Used wide band O2 meters when I ran a chassis dyno in Cincinnati years ago. A must for tuning

[redgum78]

  for the feedback guys. I ordered it today. Its going on this this rig.....Aussie Valiant Charger. Got a 400 B block with 440 crank and six pack. Hope to point it down the strip at Easter 

[flyinlow]

I have an AEM kit. Used it for a few years, no problems.  F.I. now , but saved it for tuning other cars.

Once your car is set up you can remove the sensor until needed again to save wear and tear.  I was concerned about the carb which hits both ends of the indicator at times and longer set times (winter).

[Paul G]

You will find that tuning with the wide band is hands down the best way to get the carb dialed in. Now, there is a whole lot more to it than just jet changes. My experience has been with the holley dual feed carbs. Edelbrock, and thermoquad carbs are tuned differently than the Holley style carbs.

The A/F ratio gauge will feed you numbers. Determining what those numbers should be is the key. How to get the carb to lean or richen at the different points during acceleration is the tough part. Tuning for a nice lean cruise condition helps mileage, but may lead to stumbles and rough running. Tuning for the just right ratio under full throttle may lead to problems at cruise speeds.

The carb can be dialed in pretty close to ideal for all conditions with a lot of reading up on how a carb works, and some trickery with tuning the many fuel circuits in the carb.