There is a guy on the Elise Talk forums who had this to say about the 0w40:
Elise talk guy said:
In dyno tests against other oils on a turbo Subie it came in first. It beat some 0W20s IIRC.
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Now, power and economy are not the same, but related. I sent him a message asking him what other oils were tested, here is his reply:
same Elise owner said:
I didn't do the testing. It's not online it's from a book by A. Graham Bell. About 6-8 top oils were tested.
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Since the oil is 505.00 rated, I plan on trying it out in my
2003 golf. I kinda would like to track down the book and see what other oils were tested, though.
*note, names were changed. I haven't asked his permission to quote him, and don't want to get him in trouble. But lets just say he is well respected there and NOT a moderator. Please pester me before him as I do go through that site and post from time to time and don't want to get in trouble or get my good friend and elise owner who uses that board as we use the tdiclub in trouble. Thank you, daBooj
**further notes: I know that this type of information would be strange to publish in a book, and that it would be even stranger for it to be from a guy named A. Graham Bell. This came from the internets. After conferring with a friend, the guy who sent me this information usually gives out good information, but is slightly paranoid. He very well may have dished out a false reference, but the oil test was done. He posted that part on the forums.