Martin_vtec

iTrader: (1)

so im running 94 as much as i can but when i put 91 in i always use octane booster, but i was wondering if using the octane booster with 94 would be a good idea or jsut going over bored lol.. it would be like 97 oct.

is this a waste or will it be good for the car

D.T.P

too high of octane is not good for a car also. i noticed with my d16z6 that 91 works better than 94. my buddy tried running 91 and 94+octane booster and the track and both times the times were the same. not sure about the affects on the motor.

Polkaroo Killa

^^ How can it not be good?

I thought the higher the octane, the cleaner the gas is and it also burns more efficiently too? Am I missing something?

Martin_vtec

iTrader: (1)

i was jsut wondering if it would be bad somehow i didnt think it would but is there a point or is 94 hjsut as good

seanv98

Unless your motor actually needs octane that high, your wating your money. What's your motor set-up?

D.T.P

ah i do not remember exactly but my dad was explaining this to me a while ago. since back in the day he used to modify cars to run on lower octane gas, it has something to do with engine internals. ill do some research or ask my dad tonight and get back to you guys.

Fr0z3N

the lower the compression the less octane needed, the higher the compression the more octane needed.

more octane then less can never harm your engine

DumbasSi

Certain high performance engines benefit from use of high octane fuel and it is recommended that you use a higher octane fuel. My Si requires 91 and runs like *** if I use anything lower. For other normal engines, using a fuel with a higher octane rating than the vehicle requires sends unburned fuel into the emissions system and cat converter. A lower compression engine cant burn it.

fingolfin

wrong..
turbo's run low compression, yet they need higher octane to prevent pre-combustion, or knocking

OP- you don't have an adjustable fuel map/ chip, so its not like your car knows you're running higher octane fuel..

you're wasting your money.. just run regular/ or whatever the engine calls for.
I could go into more detail, but just my word for it

MPR

ugh...


Ok, here's the truth about octane:

Octane does not make your engine make more power.

All octane does is resist detonation or pre-ignition. The higher the octane, the stronger it's resistance to detonation.

Detonation is bad, it can cause your engine to blow. In higher performance engines with higher compression or forced induction (which creates higher combustion chamber pressures) a higher octane fuel is need (usually required) to prevent detonation.

For most stock engines, 87-89 octane is perfectly fine and you will not make any more power by running a higher octane fuel than required.

For higher performance engines like the B16A2, B18C5, ferarri engines, corvette engines etc.. that require 91 or 94+ is because they run higher compression or forced induction and were designed from the factory with more agressive timing and fuel maps which requires it to run on higher octane to prevent detonation. That is why you should not run lower than required octane on those engines. If you choose to run lower than required octane, it will retard the timing, detonation can occur causing potentially severe damage, it will run less than 100% efficiency, and you will get crappy fuel mileage.

Running higher than required octane will reap no benefits or performance gains.

Octane booster is a huge waste of money because the amount that is in that little bottle is next to nothing. You would have to add several bottles to half your take to bring the octane level of the fuel in your tank up even half a point. Ther are not as potent as they say they are.

All in all: Run no higher than what is necessary because it's not necessary and you won't be gaining any performance from doing so.

T-MacK

My K20A needs 91 or it drives like ***!
And as far as putting in octane boost your just wasting your money?? You might get an extra 2mpg.
My EG needs 94 octane because it has a 12:8:1 compression ratio and would probaly blow if I threw in regular.

Martin_vtec

iTrader: (1)

i have a b18c Bored to 2.0.. i can even feel the difference when using strait 91 my baby needs 94.. not sure comrepssion ratio i know its high tho i know how octane works buti guess ill jsut keeop with 94 rather then going over board lol

MPR

He wasn't necessarily wrong, to word it differently: The higher the combustion chamber temperature and pressure the higher the octane required.

The reason forced induction engines need higher octane yet will run lower compression is because as soon as you start forcing more air in the engine, the combustion chamber pressures are equal to or higher than that of the same engine with higher compression. That is what causes detonation and that is why it needs higher octane.

fingolfin

you're right,
wrong was the incorrect word to use. I should have went into detail about spontaneous combustion and pressure.

im sorry Fr0z3N, you weren't completely incorrect.

Fr0z3N

I wasn't incorrect at all.... go research something about turbos before you even try and second guess me. start by searching the reason why we lower the compression when turboing a car, then after you're figured that out, if you still don't have your answer search the compression levels of a boosted car while under high boost.

sp00ner88

myth busters just proved octane booster decreases car efficiaency by 5%... MYTH BUSTERS FTW!!!

RotaryPWR

i understand how octane levels work and all, but how can u tell what octane to run in a non-factory boosted car? is this something a tuner can tell u? or do u just run the highest rated gas u can find and then call it a day as long as it runs smoothly?

MPR

The best thing to do with a non-factory aftermarket boosted engine (or any significantly modified engine, boosted or NA) is to run the highest octane available.

This for both safety reasons and to get the most out of the setup. By running lower octane you wouldn't be able to tune the engine to it's strongest potential. The typical higher combustion chamber pressures and temperatures that come with built motors require higher octane levels to prevent detonation or pre-ignition.

vinnierap

i dont understand whats so complicated... If your car is NA and pretty much stock, run what it says on the car.... Or else go to shell put V-power and have a good day... I dont know n e thing about turbo so im not gonna go there...lol.. and nevermind octane boost... its a scam!!!