I can't exactly explain it, but if you use regular 87 octane gas the
computer will sense the difference, retard the spark, or something, thus
effecting optimum performance.
Somebody else will no doubt give you the right advice.
Somebody also posted awhile back over the course of a year its only $250
more if your run premium fuel as opposed to regular.
1991 Pontiac Bonneville LE
3800 V6 ( C ), Black/Slate Grey
_~_~_~_~276,925 miles_~_~_ ~_~_