Dave you just read my mind when I was about to post the same thing. Sad.. isn't it?

 

I know there is no problem with 93 octane and there might or might not be a problem with 87 or 89. To me it is worth the extra $2.00 or so per fillup for peace of mind.

 

While the price of gas increases, don't forget that the price gap between the different grades decrease (percentage-wise).

 

you could also buy 87 then buy some octane booster, get it up to 100 octane :-P Or depending where you are maybe you could buy some racing fuel, isnt that 120 octane? I'd like to see how the engine performs then.

 

OK...I have seen the error of my ways. One dumb question: if the car's ECU has "detuned" the performance due to the under-recommended octane fuel, is it safe to say that it will "tune" itself again to the old performance levels I have come to love if I put 91-octane gas in it next tank full? Please don't say that I have to go to the dealer and have them reprogram the ECU... .

 

[deleted]

Didnt' realize how freakin' OLD this post was

 

If you don't hear pinging, it is unlikely that you will damage your engine. However, depending on the compression characteristics of your engine, if you use a fuel with insufficient octane, your anti-knock sensors may be kicking in, and retarding your timing to prevent detonation ahead of the flame front as well as changing other performance characteristics. This can not only affect performance but ALSO FUEL EFFICIENCY. One also needs to be careful that changing conditions does not lead to pinging or knocking under high load conditions (like the mother-in-law in the car or driving mountain roads).

 

I understand gas is going up more and more.. but the reality is.. don't go cheap if you have a G35.. get a honda for a daily driver then

 

The "veterans" get their collective panties in a wad when a subject comes up that has been beaten to death in a new thread...I was just attempting to save some whining and crying.

 

I understand... I just responded to a post on page 1 of the thread and then I realized that that particular post was from way back... didn't wanna open up a can o' worms

 

Why by the expensive car is you cant afford the expensive gas? all you saying your paying 2.25/gallon for 91/93... YOUR FUC*ING LUCKY, here in So Cal its 3.20/gal $55 to fill up. So stop your whining and pay the extra couple of bucks for the 91/93. And on that note, using a lower grade gasoline 87/89 wont hurt your engine performance if you use it every once in a while. If you use it for a long period of time eventually your performance will drop and long term damage will be done to your engine. If you want your G to last use 91/93 if you dont use the cheap ****.

 

On the other hand, if there isn't a noticable difference, then why spend the extra money? Higher octane gas requires more oil for producing it.

Otherwise, you could argue that you should look for the most expensive gas station in town, since you bought a borderline luxury car

 

.........don't worry about them

Bringing back a useful thread is AOK -- It shows that some are searching and taking the time to use an existing resource rather than create a new one.

This thread will benefit everyone. kudos for reviving it.


Not dumb bro, it's a very pertinent/important question....
I'm not expert but from what I understand, the ECU will readjust to the higher octane and quickly.

What I'm unclear on is how far the ECU 'detunes' the timing to account for the lower octane gas.
To me this is important too, because if lower octane is used that is sold as 87 and isn't quite up-to-snuff and is stale, and/or contaminated, it would yield maybe 85 or even 83 octane which may be outside the detuning parameters of the ECU thus causing some detonation damage.
At least with 91/93 octane - if it's substandard, stale or contaminated, it's 89 or even 87 octane is sufficient and probably won't do any damage.

I personally like the higher octane even when priced highly because it contains more cleaners and will help the engine's valves, pistons, and combustion chambers as well as fuel injectors stay clean.

Something to ponder.

 

This might be a stupid question so please don't flame me, but has anybody tried using regular gas then throwing in a can of 108+ octane boost. Just a thought.

 

Hmm..
Why would u buy the G in the first hand if you cant even feed her?
less WOT = less gas burnt

cheers