Quote: I read an article about oil weights. It is interesting in that those numbers mean jack at operating temp. Strictly speaking those are for when the engine cool starts. Here is the article http://www.ferrarichat.com/forum/showthread.php?t=136052
That is a very long article, most of which can be ignored if you understand the SAE designations for oil weight and viscosity designations.
There are also some people that have replaced camshafts that would very much disagree with:
Quote: Please note that it makes no difference what oil you are using. The 0W-20 Mobil 1 that is SL rated meets the same criteria as that SL rated 10W-30 synthetic or mineral based Pennzoil. That SJ or in particular that SH oil some people are looking for (from their older automotive owners manual) is no where near as good as any SL oil of today. Always use the most currently available, highest rated motor oil, even in the oldest, most worn engine. You may require a thicker grade but just make sure it is SL rated.
I use 10w 40 in my street driven 440. Something to think about is that oils require more non-lubricating additives to achieve wide cold/hot spreads.
In other words, there are lots more additives to produce a 5w-40 oil vs a 5w-20.
