Oil

An interesting question and with a few different options, which really depends on your personal preferences, it’s a hot topic on here sometimes.

I prefer Castrol Oils, the data from 1973 suggests “ Heavy duty motor oil ( Classic ) 15W-50 “

For older cars the 10W-60 is the best option imo and the latest oil is called Castrol EDGE Supercar 10W-60. It is a full synthetic and uses the latest Titanium strengthened base oils for the best possible performance and protection.

This would in my opinion be the better oil and to use their sales blurb “it would offer excellent cold start properties, being a 10W would allow easy cranking and fast starts – with faster transition from boundary to full film lubrication. At working temperatures the 60 offering a slightly thicker fluid film between all the moving surfaces, but being a synthetic, the frictional characteristics would be less than a basic mineral 50 grade so would flow better and be more efficient”

Also the full synthetic would keep the engine cleaner and be more resistant to breakdown under temperatures and loads.

If the engine has been well cared for, and isn’t worn or full of sludge or deposits, then I see no reason why a modern full synthetic is not desirable as it is derived from mineral base stocks and is fully compatible with the old classic 20W-50 mineral so will be no more an issue with seals etc than a mineral or part synthetic would be. If the engine is worn and uses a little oil, the extra viscosity of the 10W-60 may also prove beneficial

Of course, if you do not want to use a full synthetic and have a preference for a more basic oil as I did– then the other options as I see it are –

Castrol Power 1 4T 15W-50. This is a part synthetic oil designed primarily for motorcycles – BMW boxer twins mainly – however, it carries an API SL petrol car oil rating meaning if you ignore the label it’s a very good part synthetic option and meets the specific Ferrari viscosity from 1973. Being a part synthetic means it will offer some of the benefits of a full synthetic, but with some of the features of a mineral ( ie. cost )

a basic Classic XL 20W-50 mineral oil and is a low detergent mineral oil is also quite suitable for the 246 and in my opinion a better bet if you have a preference for a 20W-50

A little note on ZDDP -Modern synthetics, particularly the thinner one ( 0W-30 ) suffered a reduction from around 900 to 6-700ppm. Bear in mind its not just the zinc, modern formulations have much higher strength base oils and other additives in balance as well so the oils are better than they ever were anyway.

If you think about zinc – adding more doesn’t increase the protection, but in effect makes the protection longer lasting. To use a simple analogy – imagine the ZDDP as thousands of tiny firemen floating round in the oil – as long as the oil does its job and keeps all the metal components apart, they are not needed, so it doesn’t matter how many firemen you have. However, if you get a break in the oil film which allows metal to metal contact – a fire starts and the firemen all rush to put it out ( the zinc activates and creates a sacrificial non weld surface at the point of contact – so protecting the metal ) during this exercise, some of the firemen are lost, but there are still plenty of firemen in the oil to last the service life of the oil. So, having more firemen doesn’t mean its more protected, just they last longer in service ( if they are needed at all ) Actually having too much zinc is worse than not enough as it can create pitting on certain metals.

I now use the EDGE 10W-60 as the zinc in this nominally 1000 ppm which is plenty, however you now need to consider frequency as I change the oil every 2 years or 5000 miles. It has always been every 2 years as I have never done more than 5000 per year!

 

Very interesting, Tony. Thank you.

I have been using Redline 20W50, which has been well reviewed and has high ZDPP (not as essential in an oil with good protection qualities, I gather from your post). I was considering Motul and Amsoil too.

If i can get Castrol here, i will be interested in the 10W60 you describe. I live in a hot country.

Andres

 

I used Brad Penn 20W-50 in mine. Partial synthetic, good stuff, highly recommended. Can get it at SOME WalMarts, and always at Amazon.com.

D