Here's an update on my engine replacement. I'll never know what happened to the original motor since it's been shipped back. The dealer somehow lost all the photos of the damage and seem to dance around all my questions when I push them on it. Oh well at least I have a new motor and 2K kms of warranty left. The more I run it through my mind and remember what it sounded like when it happened I am positive it was detonation that killed it. I've only ever run 87 octane and two weeks ago I switched to 91. Since then my mileage has gone from 17-18L/100km to 13.5-15L/100km. I think that's about 14mpg to 17mpg but not sure. It runs better, idles smoother, and feels more responsive. I plan on putting the HPS intake back on when I put my summer wheels on and will be running 91 octane from now on. Just my two cents.