Michael: It is not a good idea to use the wrong octane recommendation for any given car- only what is recommended- using the higher octane rating only leads to 'carbon build up" in the cylinder head and then knocking!! All of which requires a few additions of "BG44K" to rid that junk- and then you can once again return to the 87 octanes !!

I know this from experience-and the addition of BG44K on a somewhat regular basis does help keep things clean- ( I ran that car up to 300k miles before donating it- it still ran OK, too)

Steve Meinecke
Franklin, Tn