how do i know what octane is recommended?

[green97gt]

how do i know what octane or grade of gas to use?

is there a sticker somewhere? or???

car in question is a 97 legacy gt 2.5

probably a dumb question. but just wondering what is recommended

ive been using regular without any noticable issues. my father only runs premium in his SVX

what do you all use?

[2.5GT]

87 I believe. I run 89 all the time, no matter what brand of gas. It almost seems that 87 burns sooooo quickly and the car felt very sluggish with it.
And occasionally, i get the Shells 93 and 1 can of seafoam :grin:

[jey]

+1 on 87.

I run 93 but I have a turbo.

[rougeben83]

87 is fine. Only reason to get 93 is if you're tuned for it...

[ShadowGT]

I run 89 mid grade. 87 is safe though
I just run mid grade because I have some mild mods to the engine. Occasionally I'll run premium when the price drops or I'll toss in some injector cleaner / octane boost because I can feel a difference in how the car runs. That and the obvious keep the injectors clean and whatever.

If I go on long road trips I will run premium gas.

[Huffer]

how do i know what octane or grade of gas to use?
is there a sticker somewhere? or???
car in question is a 97 legacy gt 2.5

It's in the owners manual, if you have one.
I have a spare one for a 98 GT if you want it, $5 shipped. It's in fair condition, considering it's had 4 owners.

[ouch1011]

87 is recommended.

Running higher than that will only help with anything if you are experiencing detonation on 87 octane. Because our cars have knock sensors, you'll probably never hear the detonation, you'll just notice that the car feels sluggish with 87 octane and better with 89. But, that just means your car has some other problem (likely carbon build-up) that is causing the detonation and running higher octane fixes the symptoms but not the problem.

Running higher than recommended octane can actually cause problems like carbon build-up and hard starting. You'll also probably notice a decrease in gas mileage because higher octane fuels often have less usable energy than lower octane.

[HeresMyMind]

i have been putting in 93 octane since I did the tune with the SAFCii just to be safe. but i have noticed a slightly harder start. maybe thats the issue

-B

[massdrewski]

this must be the crack speaking but....I thought I read in my owners manual for my 98gt that 91 is recommended. am I wrong?

[Huffer]

this must be the crack speaking but....I thought I read in my owners manual for my 98gt that 91 is recommended. am I wrong?

yep, you're wrong - unless your manual is from a different country that uses different octane ratings.

[Legacy89]

In my manual 95 is recommended, tough 95 is the lowest. 99 is the highest. I always run on 95 Shell V-Power. No buildups in the exhaust or the pistons.
Also use octaneboost and injector cleaner from time to time.

[ouch1011]

The US uses different octane ratings than most other countries. The numbers are lower, but the actual anti-knock qualities are the same.

I think 91 is recommended for the 96. All other years recommend 87.