[Blue]

http://www.carsguide.com.au/site/news-and-reviews/car-news/fuel_substitution_futile

[2i30s]

ive noticed the difference in cars ive used premium in,its not just a placebo afect.

[Blue]

I run high octane in my petrol cars too.  I swear by them.
That's why I thought it was an interesting article

It does explain why some cars, like POS Falcadores, don't get any benefit from the higher octane.

[snowcherry]

i think for me, whose knowledge is relatively minimal, it makes me a bit confused again


like i sorta get it, but i don't. the i30 in the book or somewhere is rated for RON91 but the general acceptance here is that it will run better on a higher octane. if someone asks me right now how i know i can run 98 in it, well i don't have a damn clue 

[Blue]

I think its about the engines themselves.

Some of them can squeeze more from high octane and some can't.
Relatively hightech engines (like the i30's) seem to be able to get more from it, I know my 24 valve V6 does !

Older technology engines, like the clunkers they stick in the Falcons and Commodores, can't get the benefit.
That's how i see it.

[diablo]

I noticed this article a couple of days ago -

http://www.autoweb.co.uk/article/631

It must be an old article as Optimax has been rebranded as V-Power for some years now, but it was interesting to see that "In a review of 95RON unleaded across 48 different outlets, the actual octane rating varied enormously between 91.8 and 96.6RON". If the average was less than 95 then going for a higher octane fuel would probably give some benefit.

I noticed that using a higher octane fuel in my Renault Laguna (which recommended 95 minimum in the handbook but had 98 on the fuel flap) had benefits for acceleration and economy - though balanced out by the extra cost.

I'm wondering if a higher octane would be useful for my 1.4 i30.  Will the Bosch ECU alter the timing to make best use of it - or will it just use the knock detector to turn it up to the same level as with 95?

In the old days a car with a compression ratio of 10.5-1 would have needed the highest fuel available - quarter pound of lead in every gallon.

I may try some V-Power when I fill up for the second time, tee hee. We need someone to test their i30 on a rolling road with different fuels. Any volunteers?

No,  I thought not. 

[Shambles]

Hi Diablo, welcome aboard.

I haven't got a clue what you're talking about but seeing as you're in Blackpool I might just pop along at lunchtime and we can go for a pint... then you can explain it all

[IMCRZY]

1 week i put in 91 ron and the other with 98 ron.....

Thats does me fine lol.....

[simon@mgr]

When the octane changes, the speed at which the fuel burns changes, so the timing has to change also.
When I was in the RAAF there were different timing settings for each type of Avgas, the same rules apply for cars.

[Surferdude]

THat's an interesting article and appears to be well balanced.
I note a comment above that the engine neeeds to be able to adjust itself to higher octane fuel for it to be of benefit. Sounds reasonable.
Does the i30 do that?

IMO the main benefit coming from higher octane fuel than that recommended is a cleaner burn which will help reduce or clear clogging in the injectors.
An EFI Injector Cleaner every few months or so does the same job, more specifically and more cheaply.

[Kimba]

Ok I was just browsing and saw this and even though it happened awhile ago I think I might have my say.

While I was running my skyline I decided to put 98 octane fuel in and I didn't look back, the price might be expensive but I found that it lasted longer than regular fuel and my car didn't seem to struggle through my drives like it normally did.

I'm going to start filling up the i30 with 98 because after all my driving yesterday I burned through a quarter of a tank already.. My skyline used to go 2 weeks before needing a refill..

[agentr31]

the skyline would have loved 98!!! i used to run shell 100 in it when i did track work! the only problem was i would use half a tank to get to the tracks i went to, then half the tank while there

98 will benifit it, dont forget it does have the "cleaning additives" (even though petrol is a solvent LOL) a higher octane is good to a point, there is only so much compensation the computer has! it can only move the timing forward to benifit it soo much, what you will notice is it wont "ping" up hills ect ect, probable gains in fuel economy too!

*shrugs shoulders* i only run 98 in my maxima and motorbikes! doesnt hurt and its not much more (although i cant remember the last time i looked at the price of fuel)

i dont know exactly what the compression r

[Kimba]

(although i cant remember the last time i looked at the price of fuel)

I'm hearing you, I just prefer to just fill it up and pay the money without looking at the price but I have never really spent more than $80 filling up every two weeks which I think is pretty good

[agentr31]

thats bloody good aye!!

that cash in my old skyline would get around 600~650 km if i didnt flog it like mad (manual,turbo was kinda hard not to )