I wasn't pointing direction as to who is wrong here. Just that there's alot of bad info. That doesn't mean everything is wrong. Just there's such a difference of opinions here it could get quite confusing for the people who don't understand or actually know.

I don't need the link to understand anything. I'm fully informed of the entire "octane rating" system, but atleast it will give others direction as what to expect.

 

No worries, I hope I wasn't coming off as brash. Please don't sick the spartan squirrel on me!

 

I use 89 octane right now, if i bump it up to 91 octane every now and then it won't hurt the engine will it?

 

yea, no joke.

I agree. If your gains are real, you might have a lot of carbon buildup causing knock or knock retard. Run some seafoam through you motor a couple times, might make all the difference.

just for the record,
higher octane DOES NOT increase power unless you can make other changes to take advantage of the higher octane (i.e. advance timing, etc).
All higher octane does is keep the gas from exploding, that's it, nothing else. if your engine is not knocking or retarding timing due to knock, you don't need higher octane. in fact, higher octane gas might have lower energy content as alcohols are sometimes used to increase octane.

the hemi is designed for 89 octane. going lower will cost you power at higher speeds/loads because the engine can't advance timing, going higher octaneprobably won't gain you anything. obviously a tuner changes what you need.

the reason race engines use higher octane fuels is because they have higher compression ratios. higher compression ratios tend to cause knocking by making gas auto-ignite (think diesel). knocking=bad

cool fact: by the end of a run, the engine in a top fuel dragster has used up the spark plug electrodes and is running like a compression ignition engine because it is running so hot, it auto-ignites the fuel. that's right, top fuel engines are 1/2 diesels.

i suspect nitro methane has a high enough octane that it still doesn't explode, but actually burns. or maybe not, the engine gets rebuilt anyway right, so let the damn thing explode. they do sometimes shoot parts of the engine out the bottom...

 

i've never tried it but i've also heard that to prove the entier higher octane = higher flash point if you take a small can of diesel you could throw a lit match in it and not **** will happen. idk wurr i heard that but makes sense diesel is like 130 or something cetane rating.

 

diesel is 130 cetane rating?! umm, not quite, its around 42-46

it's not so easy to light gasoline either, but you hold a match to the VAPOR from either (not the liquid fuel), and it will light

 

Good info, someone knows what they're talking about. I've personally put out cigarettes in gasoline. It's all about fire chemistry!

 

Just get a Predator and keep running 93
Higher octane is less apt to preignite, and is works better under higher cylinder pressures. Too much octane will actually make less power.
I tried in in the Mustang. Ran 114 octane racing fuel and lost 2/10ths in the 1/8 mile because my engine is only 9 to 1 compression and runs best with the timing cranked high and 93 octane.
It did smell good though

I agree, you got the added power from 100% gasoline instead of the 10% ethanol crap they try to sell and many places. Stick with 89 without a tuner.

 

Thanx, I didnt want to start a fight about octane ratings, but it turned into that.
I just have to remember to never get gas where i got the sh*tty 87. I also noticed today that my gas mileage monitor went up .3, but that could be that its nots so f*cking cold and i dont have to let it run for 20 minutes in the morning