91 v 95 v 98 Octane..

[TranceZiggy]

Thought this was a noob question, so it should go here..

Searching for the difference between the different octane fuels generally only yielded results about whether you get more kpl (or mpg..) with 98 RON as opposed to 91 RON & whether this increased kpl offsets the cost etc..

I'm not bothered by this. From what I've seen (tried all 3 RON's), theyre about the same in terms of kpl.

What I would really like to know, is whether 98 is any better for your engine in terms of performance & general engine health than 91 or 95.. I drive an EK1, so the minimum recommended RON is 91, however, since purchasing it, I've only been running 98 or 95, 91 once or twice.

I don't know if it's just in my head or not, but it feels to be a bit more responsive on 98 & generally sounds like it's running smoother.

Does anyone know whether 98 RON actually does improve performance &/or improves long-term engine health?

Oh and, Ethanol is just plain bad. Leave that crap out of this, lol.

Cheers..

[mugen_ctr]

91 = cheap and cheerful

95 = its ok, could b better but usually cheapskates will use it cause they think they are saving money over 98

98 = best we got, performance and get more kms outta a tank, though usually ur car has to be tuned for it to maximize the full potential of the fuel, most cars tend to run better on 98, even if they are tuned for 91, but yes 98 is the way to go, its cleaner fuel, burners cleaners, smells better, has much better anti knock properties etc etc

ethanol, unless specified by car manufacture, than dont touch it as it might eat out ur rubber fuel lines

[integragsi96]

98 = best we got

not entirely mate.
some places sell 100 octance but its hard to find.
if your car is tuned for it e85 is better.

[mugen_ctr]

not entirely mate.
some places sell 100 octance but its hard to find.
if your car is tuned for it e85 is better.

true that, but generally most places 9/10 wont, although i do remember mobil used to do it ages ago, and before they got taken over...

And E85, shiiiet some of the power gains are pretty good... if tuned right that is hahahaa

[TranceZiggy]

Yeah cheers guys.

I actually care about my EK, so I'm gonna be sticking with 98 to keep it running nice & healthy. Plus I like the increased response that I've noticed .

I've seen some places advertising 100 RON, but it's Ethanol crap.. Haven't seen any legit 100 in SA. There's even 96 RON, but again, Ethanol..

[curtis265]

There is not much point running 98 if your car's not tuned for it. The stock ECU can advance the ignition timing a little but it won't make that much difference unless you're properly tuned on it's knock resistant properties. The only benefit is that the 98's a little cleaner than the others as they add more detergents to keep your intake path clean.

You also have to constantly use 98 to see benefits. The ECU adjusts slowly

I can't tell a difference between 98 and 95. I suppose my butt dyno isn't very sensetive.

[kenny07]

i thought ethanol is like an octane booster... welll from what ive read..

... or maybe i read it wrong?
well dont know..

they go its fine for your car so long as you change the oil filter regularly..

i pour the 100 premium from united petrol and its got 10 percent ethanol in it

car runs fine and feels abit more smoother and responsive than 98

[FAITHLESS]

They were talking about E85 which is 85% ethanol and is only for use in particular cars built for the fuel. Makes big power.

[kenny07]

They were talking about E85 which is 85% ethanol and is only for use in particular cars built for the fuel. Makes big power.

yeah i know about the E85 tune on particular cars, but i was referring to the first comment...

"Oh and, Ethanol is just plain bad. Leave that crap out of this, lol."

so yeahh

[EJ1]

With E85 the price is somewhat cheaper but at the same time you will notice a rapid increase in your fuel consumption. Trying to source it is the only hard part in some states as its not readily available as opposed to 98ron.

[TranceZiggy]

There is not much point running 98 if your car's not tuned for it. The stock ECU can advance the ignition timing a little but it won't make that much difference unless you're properly tuned on it's knock resistant properties. The only benefit is that the 98's a little cleaner than the others as they add more detergents to keep your intake path clean.

You also have to constantly use 98 to see benefits. The ECU adjusts slowly

I can't tell a difference between 98 and 95. I suppose my butt dyno isn't very sensetive.

Well, point is, I generally put $30 in my tank every week, whether it be 98 or 91, I still pay $30. 91 makes my fuel gauge go up higher, sure. But 98 lasts just as long as 91 does, I don't find myself needing to put a bit more in when I'm running 98, which tells me that the ECU/Injectors are doing their job & squirting less fuel in when running 98 to keep optimal oxygen/fuel ratio. (As far as I know, 98 is a little denser? And thus the injectors use slightly less fuel to maintain optimal oxygen/fuel ratio? Don't quote me, I'm no expert.)

So, I get the same mileage with $30 of either 91 or 98 on my 'untuned' EK, so I basically choose between my fuel gauge going up higher (91), or knowing that the 98 is burning cleaner & keeping my intake clean.

Plus, as you said, over time my ECU will adjust slightly.. Providing slightly better performance eventually.

[amant02]

i thought ethanol is like an octane booster... welll from what ive read..

... or maybe i read it wrong?
well dont know..

they go its fine for your car so long as you change the oil filter regularly..

i pour the 100 premium from united petrol and its got 10 percent ethanol in it

car runs fine and feels abit more smoother and responsive than 98

And killing your seals at the same time.

I was under the impression that ethanol damages the motor, as its slowly eating up rubber seals, fuel likes etc etc also from memory year12 chemistry ethanol burns at a higher temp.

Using E10 in my dads camry did made it feel smoother in the lower rpms but felt like shit at higher rpms. Barely got the KM/L that using 91 or 98 offered in it.