I've got gas

[Jtownman]

If I've been putting in 87 for like, a month now, would it be ok to start putting in a higher octane?

[deviant]

i'm assuming you have a gt because if you've been using 87 in a gt-s for that long you'd probably have had some problems by now. simple answer, you can use higher octane at any time on a car, you don't need to "break it in" on a lower octane.

[Mayhem2k]

yea i hope you dont have a gt-s

[Blue Bomber]

Putting in higher octane won't hurt at all, but don't expect it to do anything performance wise.

[POISONLOTUS]

Originally posted by Blue Bomber
Putting in higher octane won't hurt at all, but don't expect it to do anything performance wise.
I don't get any extra HP from using 91? :chuckles:
You really can't use 87 in a GT-S? Why does it differ so much from the GT?

[Kuz]

higher compression...

[POISONLOTUS]

But I didn't think it was THAT much of a factor...

['04-GT]

Originally posted by POISONLOTUS
But I didn't think it was THAT much of a factor...

It is the determining factor.

[Blue Bomber]

Originally posted by '04-GT
It is the determining factor. :werd:
The higher compression of the GT-S makes it more likely for gas to set itself off before the spark. Higher octane gasses were made to handle higher compression, and last until the spark plugs go off.

[F35-JSF]

You'll probably see slightly better fuel economy with higher octane. Originally posted by Mayhem2k
yea i hope you dont have a gt-s

As do I.

[Burrcold]

Originally posted by F35-JSF
You'll probably see slightly better fuel economy with higher octane.

As do I.
exactly..although the price of higher octane would surely outweight the better fuel economy

[LongBeachRacer]

What kind of serious problems can arrise from 87 octane in a GT-S? Is the occasional 87 octane ok or no? How about extended time?

[Blue Bomber]

No real problems in the short term, but the predetonation would eventually kill your engine if the ECU couldn't adjust the timing enough to compensate. You'd also lose some power since the timing would be stepped back.

[MISTER 2]

Originally posted by LongBeachRacer
What kind of serious problems can arrise from 87 octane in a GT-S? Is the occasional 87 octane ok or no? How about extended time?

You should not ever run 87 octane on a GT-S. If you do the ECU will retard the timing and the engine will run like crap and make no power. Your knock sensor should put the car into a limp mode and prevent any serious engine damage. But if you want to use cheap gas don't buy a GT-S.

If you run 87 octane in a high compression engine, or engine running boost you risk detonation. When that happens you risk destroying all sorts of things like head gaskets etc.