Shell 95 ron unleaded

[Pom Down Under]

Whilst filling up my shed tonight I noticed that Shell/coles Express are now selling a 95 ron unleaded petrol (it seems to have replaced the LRP hoses at the bowsers).
It was selling for $1.11/litre, regular 91 ron was $1.05 and Optimax was $1.15.

Has anyone put the 95 ron in their MINI and if so what effect did it have?

I was a little suprised as I hadn't heard it was coming in.


Phil

[Todd!]

I thought optimax was 95... I have not noticed. Maybe they have got Optimax to 98 like Ultimate...

[minigolf]

Optimax has always been promoted as being 98RON. AFAIK it was the first 98RON fuel on to the market in Australia, by some margin???

I did read somewhere that Shell was replacing its regular ULP with 95RON, looks like they've started.

[okapi]

optimax has been 98 (vortex has been for a little while) since i've been in oz. took me by suprise - RM2 vs. RON



i'm sure andrew is beter at answering these sorts of questions, but it's my understanding the ecu constantly adjusts the timing to prevent knock and is particularly sensitive to crap petrol (mis-labeled/cut, etc.). once adjusted for lower octane petrol, it takes a while to get back up.

i'm sure the 95 is much better than 91, given no choice. in the US, there were lots of petrol tests (i come from the land of CARB). where the manufacturers recommended regular unleaded (RM2 87), higher rated petrol didn't make a difference (performance, emissions, etc.). mid grade came out (RM2 89) which was supposed to be 'better'. Well in a non tuned car, it offered no benefit. in a car where the manufacture has recommended 'high grade' (RM2 92), using 87 was in most cases not enough to prevent knocks and pings.

[MickyD]

optimax is an average of 98

Ultimate is a minimum of 98.

Optimax also has about a couple of hundred times the sulphur of Ultimate.

[KGB]

Quote: Originally Posted by MickyD

optimax is an average of 98

Ultimate is a minimum of 98.

Optimax also has about a couple of hundred times the sulphur of Ultimate.

so Ultimate it continues to be then.

Thanks Micky.

[Todd!]

Im not convinced... we use Shell here and I think it runs far better in all of our cars.

Ultiamte fouls plugs on the Cobra... so that never gets used. Whne they dyno's the motor in the cobra it made 4 more kw with Mobil Synergy 8000 than Optimax... so who knows!?!

[mamba]

I've just run my first tank of 8000 and its given me consistant milage left in tank to be 30km more than the Ultimate. Will see how the second tank of it runs when I fill up today or tomorrow.

Haven't touched the Optimax yet....

[okapi]

excellent info, Micky. i' guess that's worth a few not having discount vouchers.

FS - 30ish litres of 98 optimax - hardly used...

(note, not really FS - please don't move this post)

[Rampant Lion]

Quote: Originally Posted by okapi

excellent info, Micky. i' guess that's worth a few not having discount vouchers.

IMHO the Vouchers are useless when buying Premium, the Shell's/Caltex's in my area frequently have prices that are 1.5- 2 cents higher than Mobil or BP anyway, so when you get up to paying 116 to 118 a litre a saving of 2c per litre ($1.00 in a MINI) is negligible when you get to choose between Ultimate/8000 and Optimax/VORTEX98...

[AndrewH]

Quote: Originally Posted by MickyD

optimax is an average of 98

Ultimate is a minimum of 98.

Optimax also has about a couple of hundred times the sulphur of Ultimate.

My understanding is that it really depends where you buy it as the oil co's do deals where a competitor will supply petrol in markets where they have a closer refinery. I think this means that in NSW (Sydney and Canberra) a lot of the 98 RON probably comes from the Shell Clyde refinery or the Caltex Kernell refinery.

There was someone here who had something to do with petrol refining in Australia wasn't there??

Quote: Originally Posted by okapi

but it's my understanding the ecu constantly adjusts the timing to prevent knock and is particularly sensitive to crap petrol (mis-labeled/cut, etc.). once adjusted for lower octane petrol, it takes a while to get back up.

There's two parts to this, first is the constant adjustment of the timing which it will to in real-time regardless of what petrol you put in. The second part is the adaptive logic which adjusts fuel trim over a longer period of time to get the most efficient air/fuel ratio in response to changes in fuel grades, altitude, air density etc (based on O2 sensor readings). I don't know for certain, but from what people have posted here, the adaptive logic values are based on long term (couple of hundred k's) averages so if you put 95 RON in your tank (instead of 98), it should have adapted by the time the tank is empty. When all said and done though, the effect of the adjustment of the fuel trim is at the margin in terms of its effect on performance and is more to do with ensuring the most efficient and environmentally friendly combustion. I think the MCS engine (with its 2 MAP sensors, dedicated knock sensor and 2 02 sensors) is pretty well able to deal with a fairly broad spread of petrol octanes even as low as 91 RON (if your really desperate).

Sorry, I'll stop crapping on now

[KGB]

Quote: Originally Posted by Rampant Lion

IMHO the Vouchers are useless when buying Premium, the Shell's/Caltex's in my area frequently have prices that are 1.5- 2 cents higher than Mobil or BP anyway, so when you get up to paying 116 to 118 a litre a saving of 2c per litre ($1.00 in a MINI) is negligible when you get to choose between Ultimate/8000 and Optimax/VORTEX98...

The good wife has lately been coming home with fuel vouchers from independant supermarkets, where she buys the really tasty stuff, and they are all aligned with
BP, 4c/lt discount.....happiness. Try it....

[MickyD]

/me strokes company fuel card

[Pom Down Under]

Many thanks for all your usefull info.

I believe the IGA supermarkets are alligned with BP on the discount vouchers and the fact there is a BP servo two minutes from home is a bonus

Also I would rather chuck my hard earned wedge towards a British company than helping to support the Dutch!!


Phil

PS - Only 17 days to go!!

[AndrewH]

Quote: Originally Posted by Pom Down Under

Also I would rather chuck my hard earned wedge towards a British company than helping to support the Dutch!!

As good a reason as any I guess