> I suspect that it is related to the functional area of the frictional
> surfaces, as
> you have suggested. Having enough oil to moderate temperature variations
> that you would normally encounter might be another issue.
>
> It is an interesting question. I dont think that one would have to talk to
> a synthetic oil technician. Whether dino or synth, leading lubricants
> companies probably have all the answers to the questions we have been
> mulling over. Getting a straight and unequivocal answer may be another
> thing.
>
> You may remember that when GM came out with the 4 cylinder Fiero, they had
> a small oil sump, 3.5-4 quarts or suchlike. Very quickly they recalled
> these cars and
> refitted with a 5 quart sump.

2 banks of 4-cyl almost certainly have much more if not double the
total friction area compared to a single bank.
Using less than a litre of additonal oil to cover that extra area looks
like the oil needs to work harder, meaning their additives would be
depleted faster (?)


B.