91suprat said:
thats a common misconception. actually, you want to run the lowest octane fuel that you can, without pinging. lower octane fuel burns faster than high octane, therefore you could technically lose a bit of power (probably not all that noticable) by running higher octane when you dont need it.
that being said, the more boost you push, you should, in proportion of course, raise the octane of the fuel to compensate, especially if you're advancing the timing.
also, just for the record, i run 93 octane, always. better safe (and losing a little power) than sorry...
-shaeff