Anyone using an A/F gauge in their car?

[AlanCasida]

I’m looking to add an a/f gauge to my car to help with tuning and am looking for a recommendation. It will be on a carbureted application. Thanks!

[jayb]

I used to get the Powerdex A/F gauges, then they sold out to an outfit called Ballenger Motorsports.  They were/are still good setups (I have two in cars and two on my dyno), but for some reason the price has recently gone out of sight, over $450 I think.  My son wants one for Christmas so I just purchased the one from Innovate Motorsports, their MTX-L Plus.  Seems like a much better deal at $200, and I've used Innovate's products before with success, so I assume it is a good unit.

[sixty9cobra]

I have an autometer A/F best tuning tool I ever had. I just need to understand carbs better good idle 13:1 wide open 12.5:1 2000-3000 very lean.

[jmlay]

I purchased a diy kit for https://wbo2.com/ in the early 2000’s. I have not used it in quite some time it never failed me. They also offer prebuilt units as well.

[Rory428]

A while back, I bought an Innovate AF ratio gauge for my 59, but have yet to install it. Just curious where you guys install the bung fitting. I have FPA semi shorty headers on the 428 in my 59, so guessing that it will have to go in one of the down pipes after the headers, but how far back? I guess whatever side offers the most clearance?

[jayb]

Wherever its convenient in the downpipe is fine, as long as it's not subject to getting soaked by water.  Make sure the header to pipe gasket is good.

[FrozenMerc]

I have used an Innovate setup a couple of times.  Works good, though I wish the O2 sensors had a longer life span.  Weld in bungs can be purchased from any of the big box online retailers (Summit, Speedway, Jegs, etc.)  Or, get the tap from McMaster-Carr and make your own.

They are invaluable for dialing a motor in.  To many detergents and additives in today's gasoline to accurately read plugs. 

[6667fan]

I used Innovate for about 5 years before pulling the plug on their stuff. Got into it to the point of adding in a “brain” so I could link in other sensors. Nothing but trouble with their stuff and customer service not very helpful.
I switched to AEM and have been pleased with their stand alone units. Only problem I had was the supplied sensor was of poor quality. Perhaps they are trying to keep costs down on entry level kits?
ANY unit you choose MUST be paired with a quality unit like a genuine Bosch. Yes, I was yelling there. Trying to save you grief on getting system to work the first time and continuing to work. Even with good sensors the time will come where you must replace the sensor. Might be every season, might be every three seasons depending on the fuel it sees and how many hours on it.
( unless you pull sensor after achieving final tune).
Mine stay in cuz there is no final tune, I’m always tuning.

[drdano]

I've had an Innovate LM-2 for around 10 years now.  I bought it because it has analog inputs, supports data logging, does ODBII.  It was NOT cheap at the time for the kit.  What I have found with mine is using the newer LSU 4.9 sensors seem to last longer...still on the first one actually.  I always run whatever motor the setup is installed on for at least 15 minutes to get it good and hot, all the vapor out of the exhaust before I even fire the LM-2 up.  This seems to help immensely with sensors failing or getting stuck in a warm up mode forever.  Innovate has serviced the box twice when I was having issues, but the past few years it's been pretty stable.   

[cjshaker]

Why is it that a Bosch O2 sensor will last 100k-200k miles, and probably 15+ years, in a new vehicle, but seems to fail fairly quickly in any aftermarket setup? And these cars are typically not being driven in snow and rain. It seems odd to me.

[drdano]

The new LSU 4.9 sensors are much better than the old style.  Looking back at sensors going bad on me, I'd say not letting all the moisture in the exhaust cook out before powering up the sensor was likely the biggest mistake I was making. 

[jayb]

Why is it that a Bosch O2 sensor will last 100k-200k miles, and probably 15+ years, in a new vehicle, but seems to fail fairly quickly in any aftermarket setup? And these cars are typically not being driven in snow and rain. It seems odd to me.

I think its because almost all new cars use a narrow band O2 sensor, not a wideband.  The narrow band sensors are probably more reliable.

[Jim Comet]

I run an NTK unit in my Comet. It has worked well even though I was running leaded race gas. I would recalibrate it each spring and was good to go. I did put a new sensor in 2 years ago when I switched to E85. The only downfall is this is a digital readout and the display can be hard to read on bright days.  It also has a 0-5v output so I can tie it into my data logger. Jim

[6667fan]

drdano, letting the sensor see exhaust before getting powered up is usually recommended against by the manufacturer. ( unless I’m misunderstanding your sequencing).

Another supposed plus of the AEM set up is it was advertised as being tolerant of leaded fuel. Which I don’t understand as both Innovate and AEM use a similar or even the same LSU 4.9 sensor.

[drdano]

drdano, letting the sensor see exhaust before getting powered up is usually recommended against by the manufacturer. ( unless I’m misunderstanding your sequencing).

Correct, that is the recommendation I've also tried to follow int he past with poor results.  I killed a half dozen of the old sensors trying to power up, fully heat the O2 sensors prior to even starting the engine.  I assume that moisture in the system was damaging them.  And yes, I have BBQ'd a sensor or two of the older type by accidentally leaving them in the exhaust unpowered.  The current LSU 4.9 sensor I've been using now doesn't get powered up until the exhaust in the car/bike has been running for 15 minutes and the engine is at operating temp.  I've yet to kill this 4.9 sensor and the LM-2 seems to behave more predictably using this procedure for me.