Which is exactly why we should use the search button to find old threads that have already given us the answer that we're looking for Then if we can't find anything or are confused, we can ask the question. But clearly that is not the case here, as there is a wealth of information in the archive. Apparently DJ also had his head too far up his ass to actually look at the threads I pulled up for him...one has a dynograph from road and track proving that the J30A1 loses horsepower when premium fuel is used instead of regular. Oh well.