(The Mad Doctor was standing over my shoulder while I typed the other post so I could verify I was right!) I think we're saying the same thing, Jack (and I would never be offended if you corrected me!). You can always use a higher octane fuel in a lower octane calibration (it would be a waste of money, but you could). The problem comes with the reverse. Using 87 octane fuel in a 93 octane tune can cause detonation unless you bump the timing. What I was saying is that due to the timing curve on the 93 map, you sacrifice fuel economy by messing with the timing manually.
Is that what you said, too?
Is that what I said before?
