AFR Logging

[Pstallo]

I have searched through several older posts on Air-Fuel Ratio meters, but most are at least a few years old and I noticed that a couple of people had tried a particular brand, didn't like it and switched.

Does anyone have any current recommendations for the easiest AFR gauge with logging to work with?

Primarily, even if I don't install the gauge this week, I'd like to run the extension wires while my interior is out to make it easier on me later.

[tirwin]

I'm about to install the Innovate LC-2. I tried the PLX and it was a dud. Unfortunately I'm not far enough along to give you a review but the Innovate seems to be a very popular choice.

[Pstallo]

I've looked at that. Are you inserting a separate bung for the sensor or can you install it in the existing O2 sensor bung and send an output to the Porsche computer?

[tirwin]

I'm adding a second bung and running the Innovate in parallel with a gauge. I'm not sure about the 3.2 Motronic but when I tried the narrowband output from the PLX it was not compatible with the ECU for the CIS system.

[Pstallo]

I figured that would be the best route. Do they have anything other than the 8 ft cable? My guess is that there is no way an 8 ft cable would reach from the muffler to wherever I would mount the gauge.

[toddu]

Take a look at 14point7. You get logging with the ability to add virtual gauges to any mobile device.

Todd

[tirwin]

Originally Posted by Pstallo

I figured that would be the best route. Do they have anything other than the 8 ft cable? My guess is that there is no way an 8 ft cable would reach from the muffler to wherever I would mount the gauge.

I'll look at it tomorrow and let you know for sure but I don't think that's an issue. I think you've got 8ft from the sensor to the module. I figured I would put the module next to the ECU under the passenger seat and then run the gauge wiring to there. The gauge is driven by a pair of thin wires. Maybe 22 or 24 gauge so I think you could use any similar 22-2 or 24-2 to get the length you need. It's been a while since I looked in the box but I'll confirm.

[Jcslocum]

I use the LM2 but just for tuning and logging, not as a permanent install. Works very well and I'm happy with it.

[OldSpool87]

Check out AEM Failsafe. It's logging hardware is in the gauge itself. AEM or Bisimoto make a extra long cable to go from the exhaust to the dash. It has an LED array akin to a 935 boost gauge that you can program colors to indicate AFR range/thresholds.

[tirwin]

I took a picture of the LC-2 kit. I think you buy the gauge separately. I bought it last summer so I can't remember.

On the left is the O2 sensor. To the right is 8ft of wiring to the LC-2 module. There is a connector close to the module so I'm guessing you could get an extension if needed.

Above that is the gauge. There is package with a wire inside. Nothing special about it. It's a 2 pair wire with a 6-pin connector on one end (2 unused). It looks like typical Cat 3 wiring using brown, yellow, red and black wire colors. The other end is unterminated. Easy to make an extension wire if necessary.

There is another connection in the package -- it is a 9-pin serial connection to interface with a laptop. Most laptops don't have old school serial ports anymore so you'll probably need a serial to USB adapter that is compatible with your laptop.

[Pstallo]

Thanks for the details! That's very helpful

[dicklague]

The only one to consider is my opinion and experience is the Daytona-Sensors Wego IV. It is sold by our host and you can get more information here:
Daytona Sensors LLC - WEGO IV Wide-Band Air/Fuel Ratio Tuning Aid

Out of all the units I have tried over the years, this is the best...PERIOD. Had it in my '73 2.7 MFI for 6 years and it is great. Self contained, hours of data MAP input, RPM, great charting software and great customer support.

12 foot extension cable is $28.50.

Don't waste your time on anything else.

['76 911S 3.0]

Originally Posted by OldSpool87

Check out AEM Failsafe. It's logging hardware is in the gauge itself. AEM or Bisimoto make a extra long cable to go from the exhaust to the dash. It has an LED array akin to a 935 boost gauge that you can program colors to indicate AFR range/thresholds.

Can't go wrong with the AEM Failsafe unit. Another feature that's great about these is that they do not require a free air calibration like most other units do. Hook everything up and forget about it.

[dicklague]

Originally Posted by '76 911S 3.0

Can't go wrong with the AEM Failsafe unit. Another feature that's great about these is that they do not require a free air calibration like most other units do. Hook everything up and forget about it.

How can you e sure it is accurate? How can you e sure it is adjusting for Sensor deterioration and carbon? Just trust that it will do it? Not for me. I want to know for sure

Is this a boost gauge and an AFR gauge?

['76 911S 3.0]

Originally Posted by dicklague

How can you e sure it is accurate? How can you e sure it is adjusting for Sensor deterioration and carbon? Just trust that it will do it? Not for me. I want to know for sure

Is this a boost gauge and an AFR gauge?

The connectors for the sensors have a built in resistor specific to each sensor which the unit uses to verify the proper operation of the sensor. This is constantly being verified by the unit rather than once every few months like a free air calibration does. When something in the sensor changes that skews the reading (such as carbon or deterioration) the unit will throw a fault code.

It is only a Lambda gauge but also has an internal map sensor that you can use as well.

Most AEM products are not all that great, but their pressure sensors and wideband lambda units are top notch.

['76 911S 3.0]

Here is an AEM BOSCH LSU 4.2 wideband sensor with the resistor cover removed. Each sensor has the resistor specifically calibrated for each sensor solely for the purpose of fault detection.

[nickd]

LC-2 works fine on my 964 with motronic. And it's cheap. I use the 0-1volt simulated out to feed the motronic. However, their software is impressively buggy. Was fine with just the lc-2, but after adding the ssi-4 for simultaneous rpm logging, I get lots of initial connection problems. I almost forgot what the windows blue screen of death looked like... After it connects, everything logs fine.

Not sure what benefit there is from a cockpit gauge? afr changes quickly and I definitely wouldn't want to be staring at the dash under WOT. In closed-loop mode, it just bumps around 14.7 anyway.

My .02. Good luck!

[Ds1]

I have the MTX-L and don't exactly like it, for the specific reasons of the warm-up time and the lack of auto-dimming based on ambient light like the similar AEM unit.

[tirwin]

Originally Posted by nickd

Not sure what benefit there is from a cockpit gauge?

It's a benefit for those of us with CIS systems where you can't set the mixture with a narrowband sensor and exhaust gas analyzers are hard to come by. You could argue that you don't need the gauge to be permanently mounted, and there is a lot of truth to that. However, if a CIS car starts to go lean, you'd want to know that before your airbox goes ka-bang one day. Just peace o' mind.

[dicklague]

Originally Posted by nickd

LC-2 works fine on my 964 with motronic. And it's cheap. I use the 0-1volt simulated out to feed the motronic. However, their software is impressively buggy. Was fine with just the lc-2, but after adding the ssi-4 for simultaneous rpm logging, I get lots of initial connection problems. I almost forgot what the windows blue screen of death looked like... After it connects, everything logs fine.

Not sure what benefit there is from a cockpit gauge? afr changes quickly and I definitely wouldn't want to be staring at the dash under WOT. In closed-loop mode, it just bumps around 14.7 anyway.

My .02. Good luck!

That is why data logging is so important. You can look at what was going on when you are NOT driving.