what kind of gas

[krashkhris]

my dad has a 04 gto 6 speed and I beleive they take higher octane gas. He was telling me that he "hiballs it" meaning that he uses half a tank of mid grade and a hald of high grade gas. Is this bad for the engin? I'm guessing yes, but what do I know

[MrPbody]

At 10.1:1 (static compression), it really should have at least a steady diet of 92 octane. 93 would be better... That being said, it the power is there, and there are no signs of detonation with the 89/93 mix, go ahead. It isn't hurting anything. You may be giving up a bit of top-end power, as the computer "manages" the detonation by retarding timing and richening the mixture.

[DawgByte]

My dealer said you can use mid grade 89 Octane. If the engine begins to ping, then he said to go back to high octane.A s the other poster said you may lose some grunt.

[Ridenour]

I would just always run premium. It's worth the extra money to make sure you're always feedin it the right stuff to ensure minimal KR. It's reccomended for that fuel, so I would run it in it all the time.