I have a GST 1997 Eclipse and i was wondering if 87 octance wouldn't damage the car and the car would adjust to it if i didn;'t race/ run it hard, and that would work fine iwth no consequencee, and if not waht would work the best for the cheapest

 

The octane level doesn't matter for whether you race or not. Read up on octane to actually understand it. Basically it will help determine when the fuel will ignite. low octane fuel = low compression with spark (NO boost). The higher octane ratings assist with preignition. When you stuff a bunch of air into a small space with fuel it tends to ignite early (Before the spark plug fires) thereby causing damage. I wouldn't recommend anything lower than high grade fuel.

 

ONLY RUN 91 or above or your motor will hate you and you will hate your motor when it is in peices

 

if you wanna run 87 octane, take the turbo off, throw it in the corner of the garage then drive it, other than that you need to stay 91 or above to keep it from detonating under boost
read up on detonation and you'll see why the dash says "PERMIUM FUEL ONLY" right on the guage
its there for a reason

 

There is absolutely no way you can use less than premium fuel on a turbo car. End of story.

 

Not sure if he is reffering to the Write I did or not but either way here is a big long indepth look into Detonation and pre ignition (knock) it is a good read full of infohttps://mitsubishiforum.com/m_42371/tm.htm

 

I'm really not sure why this is even a question to be honest with you....I mean, the "Premium Unleaded Only" is on the speedometer or in the gas door or even both.
I'm not trying to flame, but use common sense.
If it's cost of fuel, well, the cost of fuel is just going to keep rising, don't try to save money on fuel, because the cost of another car or a rebuilt motor won't save you anything.
Sorry to be an ***, but, come on!?

Oh and welcome to MF

 

yea thats what i was referring to, pretty good write up on it

 

aight i know about the warning on teh spedometer but my dad has a LS400 and its the same way but it has a comkputer that adjusts itself the that fuel but yes it is non-turbo so it isn't affected as much so i was just making sure aight

 

Our computer is less complex or complicated than your dad's Lexus though. I don't think it adjusts itself to the FUEL per se, but more so how the motor is reacting to the lower octane, such as knock, o2 readings, EGR sensor readings and probably a whole slew of other sensors in that car. Ours do that too, sort of, by reading knock and pulling back on timing, lol.