I agree, if your limited for sensors then you should take the reading from the leanest cylinder. If you read off all 8 then chances are the O2 is placed a fair way from the cylinders, taking longer to heat up and your getting a diluted mix so you could have a cylinder running dangerously lean.
So back to Chris's original question, is there a cylinder that normally gets more airflow?
To take an educated guess I would say the left bank might have a slight advantage because of the angle of the TB, but it would probably be marginal, if at all.
The other option is to do a few runs with it on one bank, then a few runs with it on the other bank, see if one gives a lower reading
Chrispy300 wrote:Not really IMO. Sure reading all the exhaust would be better, but with a standard ECU you can't change individual cylinders fueling so it shouldn't matter. Looking at the intake manifold there doesn't appear to be a bank or even a cylinder that would be unequally lean, unlike the VG.
As long as everything is working (injectors) as it should then it won't make a difference between reading 1 cylinder or 8.