I don't know if my mine is playing tricks on me or not, but I remember when Snow Trooper was tuning this single turbo there was some issue with having both primary O2's in the same downpipe because the ECU is looking for differences between the banks since the ECU is configured for stereo lambda.

Of course on a single turbo car this is an issue, so I believe back then Snow Trooper got around this by feeding one bank a slightly modified signal from his WB narrowband output to one of the banks O2 sensor inputs.

But for some reason I want to say that I've stumbled upon someone else running a single setup on here that has this problem resolved and running mono lambda? 

The search on this forum kinda blows and haven't been able to come up with anything other then Snow Troopers original fix (here: http://nefariousmotorsports.com/forum/index.php/topic,722.msg6469.html#msg6469 )

Any thoughts on this would be appreciated!

Yes it does, if they are the same it tries to separate them by trimming one more lean and the other more rich until its happy.  With both sensors in one pipe or a split signal from one it will trim until one is -25% and the other is +25%

Phila_dot created a hack to feed trims from one sensor that works perfect, but if your fuel rail doesn't get evenly fed from both banks it can be iffy because the second bank fed will be lean.

My professional suggestion for the safest setup is to run both factory sensors pre turbo so trims stay accurate.

My buddy who's car I am doing this on thought about doing this, I was just cautious about O2 life considering the high EGT's pre-turbine.

pic of the setup in an 03 A6 avant, went back to the stock IM for now since the TB was too far forward with the custom SMIM:

The life of the sensor will be shortened depending on what kind of egts you see.  A bit of a trade off but in the end the sensors aren't that expensive.  So far nothing else works as reliable or safe.

Perhaps you should stfu, I'm not in the mood for your snarky bullshit today.  Post up factual evidence or stop talking.  I have read the thread.  I understand what happens.  Fact is they trim away from each other if they get the same signal or one that is basically the same.

How many single turbo or single downpipe path me7.1 2.7t cars have you seen let alone touched?

^^ Interesting... although I am not in any way familiar with feedback loops, etc...

Do you have a solution for this?

What are the thoughts about running the O2's pre-turbine in the up-pipes in regards to EGT's effecting longevity of the sensors?

I would also really appreciate if you and Snow Trooper could refrain from getting at each others throats, that helps nothing.  I know it's hard sometimes when not all of the angles have been covered and not everything is easily explained.

I'm not a computer wizard like you obviously are so feel awesome.  I have always stated I barely am capable of what I do in a computer sense.  I do however understand engines on a better level than many, or so I have been told.  My theories, hypothesized instructions based of testing facts are only posted as facts when that's how I understand them after REAL WORLD results.  Only share what I know.

You and I have the same end conclusion and answer, they trim away and are different.  Thanks for being a pita.

Unlike you, if I am not sure about something I don't open my mouth. There is a distinct line between remarking observations and making up explanations, trying to pass them off as fact and then trying to pull "authority" when they are questioned. The former is helpful, the latter not so much, and you seem to cross this line without hesitation.