One bank leaner than the other?

Would someone take a look at this log and graph setup. It seems like one side of motor runs leaner than the other side? Also the left sensor is more flatline? i have dual Spartan widebands in the header collectors. both grounded to the same place. The right header secondary pipe is a little longer than the left. car runs well. 5.3l on E85 with 525ASA cam, open exhaust. thanks.

the MVPI2.2 is the right WB and the MVPI1.1 is the left.

Attachment 163250
Attachment 163251

Quote:

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Originally Posted by DaveNY

open exhaust

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probbaly your issue

describe your exhaust system please and location of sensors

If you are familiar with an IMCA DIRT car exhaust it's the same. long primary's that exit out the fenders with 3.5 collectors (widebands & narrowband in the collector), then 18" of 3.5 secondary pipe that ends about the middle of the door.

Am I mistaken or is the definition different for both WBO2's? One is in AFR and the other in Lambda and if that is correct they are both reading close to the same? Change them both over to Lambda to compare apples to apples. The NBO2's look like they are doing just fine.

The log is all at idle rpm correct? Bring the RPM up to 2500 or so and recheck. An open exhaust system is most easily tuned by ear at idle for the common man if the O2's are within 2 feet of the exit.

Yes, i custom transformed them differently. i wanted to easily see Lambda and AFR. i will probably do that and then use math to see AFR in a chart. how would i use them both to average EQ in a EQ ERR graph?

Do yourself a favor and train your brain to think in Lambda.

My first thought is to make two separate graphs, but if your wanting to add both WBO2's to the same graph and get an averaged EQ error, IDK, I don't use the software enough.

Open exhaust is going to be the problem. You need feet of exhaust behind the o2 sensor to work. Collector extensions are not going to work.

Thanks Alvin, This is actually your tune, and i'm just trying to get everything logging correctly to send you my first evaluation log. Car has run awesome from first fire-up!