vettef6

I had my tables all set using DataMaster and was pretty close +/-4% of 128BLM. A couple of days ago I installed the WB Meter from Zeitronix and compared the AFR and BLM values. Using the WB Meter I found I was running too rich, so I changed my VE table accordingly. My AFR at part throttle is now at about 14.2—14.7, but my DataMaser shows now that I’m way lean, about 128 — 150 BLM. I don’t know which values to trust. I can send the DM DA and Zeitronix file to anyone that thinks he can help. Thanks

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Z69

There was a discussion about this over on the DIY Prom board.
As long as there are no drivability issues, then the WB is correct. OR at least close. A bigger cam can throw off a stock NB. Or maybe your NB is just bad.
Also, if you're in closed loop, then the ecm is adjusting to what it thinks the NB sees as 14.7. Lots of overlap on the cam can put extra 02 in the exhaust and cause the ecm to add fuel during CL.
So I'd assume you are disabling CL to do your VE tweaks.
See the above discussion.

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vernw

One other thought before you take off changing the tuning.....

Are both NB and WB sensors in the same bank of the motor?

If not, try swapping them and see what happens.

I had the same results (and still have!) and swapped the sensors and the results went the opposite direction. Which means I have either a fuel or ignition issue on the right bank of my motor (it's running much richer on that side).

So unless the 2 sensors are on the same side, don't count on a sensor problem yet.

Just my