WOT max power lean is at 13.2:1. When you first go wot it will spike, then settle down so it sounds like your good.

If you do go to a dyno, still get them to test with a wide band o2 so you can compare the wide band readings to what you see on the ARM1. If you can't sit in the cab while operator runs the pull, mount a video camera to verify ARM1. I strap my camera mounted on its tripod to the back wall using bungee cords around the storage tray holders.
I wont quote Joe but at WOT the narrow band may not be too accurate

 

Did you use the fator O2 sensor or the sensor that you can get from split second?

I'm just wondering if the calibration of the factory O2 sensor is for 14.7:1 at the 0.45V as indicated on the split second website.

 

I am using an aftermarket sensor, but not the one from Split Second. I had to change that sensor back last year. I can't remember now what I got to replace the factory one. It might even be a wide-band, I can't remember for sure.

 

Is the stock Dodge engine control system a closed loop system? If so then it should be able to compensate for some modifications, correct?

Does anyone know how much the various inputs can be changed and still have the stock ECm properly control the engine functions? Any website that some one can p[oint ot that would have this information?

 

Dumb question, but what is the difference between narrow and wide band O2 sensors?

 

They operate in both closed and open loop.
These are the open loop modes:
-Ignition Switch Key-On Mode
-Engine Start-up Mode
-Engine Warm-up Mode
-Acceleration Mode
-Deceleration Mode
-Wide Open Throttle Mode

These are the closed loop modes:
-Idle Mode
-Cruise Mode

You mention compensating for some modification. Yes it does, but to a limited degree. These trucks are speed density systems rather then mass air flow system. MAF vehicles respond much better to mods then do speed density designs. SD's rely on a combination of sensor inputs to tell the PCM how things are doing, then it makes adjustements, but within the confines of preprogrammed tables. So, you can add all the air you like via air intake upgrades, TB's, CAI, etc, but unless you tell the pcm what to do with it (i.e change the table values for things like IAT, MAP, and fuel trims), it will only see minimal improvements. Same reason upgrading to bigger injectors is a bad idea unless you plan to flash your PCM at the same time.

It's hard to say how much you can change on a stock engine before you have exceeded the stock programs abilities to keep up. I have seen guys in other forums who are trying to break down the programming to understand what the limits are. Little progress has been made from what I have seen. You really have to just keep adding mods, and when you think they are not producing the results you thought they would, it is probably time for a performance PCM or a custom flash. That's what I did, and decided to go with the Mopar Performance PCM. It made a nice difference over the stock PCM with all other mods being the same. Once I exceed this performance PCM, I plan to get the B&G flash.

Here is how I discribed it on another forum yesterday. The difference between a narrow band and wide band o2 sensors is in how the sensor converts readings into voltage output. The stock narrow band sensor operates between 0 and 1 volt. This means it can positively identify a rich or lean air/fuel condition, but only within a range of about 12.5:1 to about 17.0:1. A wide band sensor uses a more sophisticated sensing element which enables it to produce more precise voltage readings over a wider range. This lets it identify a/f ratios from as low as 9.0:1 to highs well beyond 17.0:1