Air/Fuel Meters for Cobra--Want Your Perspective
 

I am in the process of having O2 sensors welded into my side pipes and am also switching to Berg IDA carbs on my car.

As a result, I am getting ready to purchase an air/fuel meter that I can use to help tune my engine and monitor A/F ratios on my car.

Please let me know if you have any recommendations on good A/F meters for this purpose.

Thanks,

Stentor

Hey that's a good idea the O2 sensor plugs probably look like this....
http://img85.imageshack.us/img85/7580/pipes006.jpg:D

LM-1,
Never leave home with out it.

Craig

AF Measurements
 

Stentor - I've also been looking for optimal instrumentation. All the units I've heard about, however, have either one channel (sensor) input or can switch between two channels. I've learned that it can often be important to simultaneously see mixture on each bank (would be best to see each of the 8 cylinders, but that is less practical). There can be situations where the linkage is not equally progressive for each bank, or perhaps part throttle mixture issues from opposing throttle plate openings (relative to the port/valve) on setups where the carbs are all in one direction, or other bank to bank irregularities. Any number of issues can erroneously lead tuners to mess with all kinds of carb parameters when the solution may be elsewhere. So, what A/F measuring setup can see both banks at the same time?

I also have the LM1. It works well.
Use the bungs from Innovate, they use a allen head bolt that sits flush. I welded mine in at about 7-8 Oclock on the passenger side and 4-5 Oclock on the drivers side. I then repainted with 1200 degree silver paint.
Unless I point them out, you can't see them. Make sure they are not to high, you will never get the O2 sensor in. It sticks out a couple of inches!!!!!! Also, don't put them in the bottom of the pipe. Moisture is bad.

I have bungs in both sides. I run and check one side then move it to the other side. One thing I have found, you can have the AF right, but it still doesn't run right. You need to pre adjust the carb according to its manuel. In my case, I have the BG Mighty Demo from 4 Seconds flat. He makes a very good easy to follow tune guide. After following his directions, then hooking up the meter, mine was very close.

Scott

LM 1 is good but the LM 2 is better
 

Stentor Lm-1 is a good basic meter but the LM-2 does both sizes of the motor at the same time live streams. You have to remember that even though you are working on just 1 cylinder it effects the rest of the motor too. Price for LM-1 about $400.00 LM-2 is about $700.00. You don't have to get the side pipes welded for bung any more LM has clamps that work almost as well and hook onto the side pipe exit. There is one thing I have learned from using an LM-1 sensor. The location is critical for getting a good mixture of exhaust gases from all cylinders on that bank. Putting the O2 sensor in the collector gives a good reading and the sensor gets hot fast but not the best mixture. Buy an EGT gun for check header pipe temps at each port also. Again buy a top of the line one. You will fine that you think you have a good tune up and be from 80f to 200f off from cylinder to cylinder. This is more with a single carb and manifold that a weber setup but still happens. I have used the LM-1, has limits but works good for learning basic tunes on a motor. You might fine one on e-bay but you will have no idea about how good the O2 sensor it working. These also need to be replaced over time because they loose there sharpness when fine tuneing. Rick L. Ps you already have the airflow meter for the tops?? I use 2 at a time for this.

I have a single sensor from PLX. Works great and really helps tune the mutliple circuits in a carb. If I were to do it again, I would get FAST unit though. You can read both individual cylinder banks or average the two together. Only $460.

http://www.summitracing.com/parts/CCA-170602/

AF Meter Shoot Out Comparison
 

I had the same question and found this comparison. PM me and I can email the .pdf.


http://www.fordmuscle.com/archives/2...tout/index.php ]

:D

PM Sent on PDF