[cr45]

Originally Posted by t vago

I had thought of doing just that, in order to completely shut off one bank. Ideally, in order to have a more-or-less evenly running engine, you'd want to have -X-X-X-X, where the "-"s correspond to deactivated cylinders, and "X"s correspond to active cylinders. This is to maintain, as much as possible, the existing engine harmonic arrangement.

However, the problem with this approach, of shutting off a whole bank, is that my engine has a firing order of 1-8-4-3-6-5-7-2. That translates to a LRRLRLLR pattern. If I were to shut off one bank (e.g., the left bank), so as to facilitate using the O2 sensor on the other bank, I would have -RR-R--R, which looks very uneven, and could shortly lead to destructive bearing wear or even a snapped crank.

One extreme measure would be to run the oxygen sensor on one cylinder only and spark cylinders 1-4-6-7. Alternatively, if you had a 4-2-1 manifold you could run the oxygen sensor of two cylinders such as 6 & 7.