I found this on a US scoobie site and found it very interesting although a little too technical. Thought it would be of interest.

www.clubwrx.net/forums/showthread.php?t=35715

Cheers
Simon

 

They do like their blackstone results ...

More here :

http://www.subaruforester.com/viewtopic.php?t=7987

 

Saw similar kinds of investigations going on with a bunch of Corvette owners (IIRC Mobil 1 and Redline)

The interesting point they found is they could send samples of the same oil to 4 different oil labs and get different results. Including things like the copper and lead levels. Which makes the matter of oil analysis rather confusing. Presumably it's down to the tester, equipment/testing method type, cleanliness and calibration of the test equipment.

 

I have further read that Mobil 1 is the smallest synthetic oil out there (molecule size) and is not recommeneded for older engines as it can expose leaky gaskets. I took it as don't use it...