I think that this is the updated version of his original "try". There was a thread about this technique a while ago, but this spread sheet seems to be better.
I'm going to try it out as soon as I get the car running again
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Edit-
http://ecomodder.com/forum/showthrea...g-cd-8402.html is the thread I was thinking about, but it leads to the same guys' write up on instructables and the spread sheet is the same. My memory must be going a bit wonky.