for the record Chris, since you mentioned it.
Ships do have turbochargers and to a lesser extent superchargers or sometimes both.

I have seen a full grown man standing inside a ships turbo charger (when it wasn't working).
Industries have many secrets that us the public don't often find about and 1 is oil and which is the best. Some others are like how some processes use machines with 1000's of
PSI boost. (THINK ABOUT THAT).

Truth is if you find an oil you like, use it.

yes i realise that ships do have turbochargers/superchargers but i am on the understanding that their lubrication system is seperate from
the engines lubrication system?
sweet as.
choice from chris

I was a Machinist Mate in the US Navy for a bunch of years and worked in the enginerooms. The oil in the turbines is major different from automotive oils in that it does not have any
detergents added to it at all. It is called 2190 TEP (Turbine Effecient Petrolium). There are twm major reasons that the TEP lasts longer than automotive oils. (1) it does not have the
carbon deposits from the fuel to contaminate it. (2) It is being almost continuously run through what is called a LOP (Lube Oil Purifier) that mixes it with water and sends it through a very
high speed centrifuge to separate the oil from the contaminates. The oil is not being used constantly though, there is a settleing tank that stores the half of the oil and it can be pumped
into and out of the turbine system so only half of the oil is being used at a time. Again, the main reason the ships oil last longer is the TEP does not get the carbon contaminates from the
fuel like automotive oils.

Mareo

Thanks all, this has been an interesting thread.
It's amazing the breadth of experience that a motley bunch of Datsun owners
have.

Take it easy,
Chris.