Air/Fuel ratio meter, what are you using?

[dmcummins]

For those of you using a Air/Fuel ratio meter or CO meter, what are you using and are you happy with it? I am thinking about buying one and wanting some opinions.

I have searched and see some like the innovate LM-1 and LM-2, what are the difference between them.

Does the Air/fuel even need adjusting that often?

Are there other meters that will get the job done for less money?

[tyro]

AEM 30-4100 wideband UEGO in both my 951 and 911SC.

Interesting to see what CIS is up to. I've had a couple of sensor failures in the turbo, but the wideband in the 911 has been happy for a while.

I see Summit now has them for $218. Damn.

[DRACO A5OG]

Most prefer the LM1 but I think the LM2 has additional features and of course more dough.

In a pinch, I use my DVM, disconnect the O2 Sensor and place the Red Lead to the O2 Sensor connection and Black lead to the top of the ICV Harness Screw.

I get a pretty accurate reading, the goal to be in between 0.20 and 0.80 volts fluctation when warm. To verify I use my buddy's LM1 for fine adjustment to the Air Fuel Ratio.

In fact I use both to verify either LM1 or DVM at O2 Sensors are working properply. Sometimes the sensor on the LM1 can go bad and give you a false reading such as condensation because the car was not warmed up enough.

[Jesset100]

Shameless plug

I have a LM-1 for sale. It's in the for sale forum. Make me an offer I can't refuse.

[moneymanager]

I'd be interested in hearing from those who have used both the earlier narrow band sensors and the later wide band units. Is the difference in information quality as dramatic as it seems it should be?

[Steve W]

Don't waste your time with a narrow band unless you only want to adjust for stoich 14.7:1 for idle. Outside that there is zero accuracy.

LM-1s are simpler to use and have a brighter display. LM-2s are the current production, and have advanced capabilities to read and log OBD2 parameters. With the LM-1 you will need the accessory devices to read/log RPM, on the LM-2, the hardware is built in. The LM1 works on a serial port, so if your laptop doesn't have one, you'll need a serial to USB adapter. The LM2 eliminated the serial port and connects by USB.

[TimT]

I probably have six or seven AF meters now. MoTEc, FJO, NGK, Tech Edge(2),AEM..

Logging capabilities really can make and instrument shine, also having a narrow band output is nice..

Don't have a favorite..many to chose from

[moneymanager]

Is data logging just a convenience, or does it really enable you to notice performance characteristics you can't see without it?

[dipso]

I have a LM2. Just bought it a month or two ago. I also bought the exhaust clamp so I wouldn't have to have a bung welded.

It is simple to use, just plug and play. I am not sure of all it's functions because I couldn't get it to load properly on my Mac.
Luckily it came pre set and I just hooked it up and away it went.

Turns out my ratio was not that much off, but I wanted to check and adjust anyways.
Pretty cool little tool.

[emac]

Draco

Sent you a PM

[DRACO A5OG]

Originally Posted by emac

Draco

Sent you a PM

Replied

[dmcummins]

I ended up buying the LM-2. Its been real handy so far. But now I probably will try and tweak it more than I should.

[the911Tprocess]

I used an LM 1 to get my MFI 72 running like butter!
I fought with mixture for awhile but with the LM 1 within an hr I had it bitting anything that got close to it.

[euro911sc]

I just hard installed an LM-2 this weekend. Worked great till I got on the hammer and the line I had it connected to had too much voltage variation... LM-2 shut down protectively. Also, getting the RPM signal from the coil is a pain as you have to run a wire right next to the rest of the plug wires... Mine is currently unshielded so I have a really sketchy RPM signal that does not match my tach. Obviously, I'll be fixing that this weekend. Outside of those two minor issues it has been very easy to work with.

I have considered logging the voltage level of the car as well, but need to research if the analog inputs can handdle 13-14 volts input. This may give me insight as to the health of the alternator/voltage regulator/battery.

I have not set my mixture yet, but once it is up and running accurately then I will. For the brief time it was running, I was about ~15.5 at idle and ~12.7 at full throttle... so I'm not far off to start with and I may end up not doing anything... during warmup it leans way out to ~16 and I am assuming that this is the AAR ? adding air...

I'll be loging RPM and AFR to start. I have some off throttle burps that I'd like to get rid of so it will be interesting to see how that goes. I have also been looking into digitial fuel pressure sensors. Perhaps usefull for a CIS car like mine... perhaps not *shrug*

Best regards,

Michael

[Jesset100]

The easy way to get rpm signal is tap into the back of the tach. My wire is a foot long.

[euro911sc]

Originally Posted by Jesset100

The easy way to get rpm signal is tap into the back of the tach. My wire is a foot long.

You know I thought about that, but the tach is not even mentioned in the LM-2 manual!! I will have to pull the tach and plug the wire in there and see how that works.

Best regards,

Michael

[beepbeep]

LM1 + AuxBox + sniffer tube ...logs everything I need + then some (boost, RPM, accelleration x + y, duty-cycle, voltage etc.)

[dmcummins]

I'm also using the signal to the tach for my LM-2. My only problem is the connection with the cigarette lighter is not the best. I welded a bung on and may just leave it connected. If I go that route I will hard wire it in.

Besides AF and rpm, what are others monitoring with the LM-2?

[euro911sc]

I have no radio so I just wired into the switched power feed of the radio and then made a radio delete plate out of 16ga. steel, drilled a hole, and mounted the LM-2 to the plate. The LM-2 is 90 deg clockwise so the wires do not interfere with the passenger's space. Wires run along the drivers seat to the rear tunnel and out the speedo cable rubber boot. I could have used and extra ft. or two on the LM-2 cables, but its fine as is.

Once I get it logging AFR & RPM I'll add voltage. I was thinking about TPS, but I'm not sure how I'd do that just yet. Oil temp/pressure would be interesting once or twice. Brake tempreture and fuel pressure also fun. Steering angle?

-Michael

[dmcummins]

I was thinking of the voltage off the air fuel meter on the 3.2. Maybe the WOT switch.