Best fuel?

[cainchapman 0]

Symantics!

Look at the torque curves and forget about the actual figures.

The newer fuel has smoothed out the curve significantly.

Temperature and humidity will not have significant effect. And yes they were close.

Why don't you look at how much oxygen is in the room when you are dynoing also? It has greater impact than a 3 degree temperature variance.

A dyno should be used for trending. Every run will be different, even on the same dyno over different days.

[*sic 1]

word

[westy 614]

Symantics!

Look at the torque curves and forget about the actual figures.

The newer fuel has smoothed out the curve significantly.

Temperature and humidity will not have significant effect. And yes they were close.

Why don't you look at how much oxygen is in the room when you are dynoing also? It has greater impact than a 3 degree temperature variance.

A dyno should be used for trending. Every run will be different, even on the same dyno over different days.

Do you think this relates to a 2.5 litre?

How much do you think he will notice?

I stand by my comment.Min rating of 89 according to BMW!

The reason 98 resists "pinking" so much is because it is more difficult to ignite,just how is this going to relate to fuel economy?

The quality of NZ fuel certainly was pathetic but,it has improved since.

As for additives,if you add additives how much "petrol"do yoiu actually pay for?

This argument goes round in circles so many times,judge for your self and make your own desicion.

[cainchapman 0]

I couldn't say. It depends on how good the ECU is.

No point in running my old Morris Minor on 98 without changing the ignition timing. Performance increase versus extra cost of fuel. I'd guess it'd be negative.

With the 540, it's a positive result.

Only way to find out, is to quantify it on the dyno. Try it out, at the current cost of fuel, 2 dyno runs @ $50 each is worthwhile IMO. Then you can make a more informed decision.

[M325is 0]

V. B

6 and 12 work well.

Twisted.

Ahahahaha

[Palazzo 438]

Thanks, you answered my question perfectly.

[kiwi535 538]

You can tell by the seat of your pants...I am not saying you will necesarily(sp) get a power increase but you will get a performance increase,even my old M30 feels smoother,and more responsive and i get slightly better economy......I think my manual refers to another measure of octane

AKI is the average between mon and ron I think....

[westy 614]

The queation was,whats the recomended fuel and is it sweet to run 91?

Not,"will I get any power insrease".The answer is yes,in your situation.

There is always a small increase in power as the engine can run a more aggresive ignition curve.The increase will depend on the engines design & size.

If your happy with 91 use it!!

[*sic 1]

i would never run 91 in my car, f**k you might as well shove in a handfull of dirt too cause thats what it runs like on that sh*t

[westy 614]

i would never run 91 in my car, f**k you might as well shove in a handfull of dirt too cause thats what it runs like on that sh*t

Fair enough

[Jazzbass 1]

A friend of mine has just done quite a bit of research into this area and he claims that evidence shows the higher octane fuels actually improve engine longevity as well as giving better performance.

He's a tight as a snapper's arse, but he happily shells out the extra for 98 all the time as a result of his findings.

[Jazzbass 1]

I think the lower suphur content is what has made me decide to go with the 98:

Property Ultimate Premium Unleaded Unleaded 91

Octane (RON)(min) 98 96 91

Benzene (max %) 1.0 4.0 4.0

Sulphur(max ppm) 50 150 350

IRRC, it was the high suphur content of USA petrol which caused problems with the Al/Nickasol engines of the 328?

I have such an engine in my 528 - better safe than sorry - after all, as someone said - why pay a premium price for a great car and shove cheap petrol into it??

[OLLIE 26]

i'm all for the higher octane fuel the better!

the difference is easily noticed when switching from a 96 to BP 98.

theres some good info on this thread

[Rod 0]

My E28 will not run properly on 96 unleaded, it pinks badly. The handbook states minimum octane rating 98 RON. The old 96 leaded fuel was fine though, when that disappeared I had to run it on avgas. If I went on a trip there was a limit to how far I could go as I had to carry sufficient fuel for the return journey. BMW also made lower compression engines (and hence less powerfull) for other markets and they would run fine on lower octane fuel. Each engine will have a different requirement which is dependent on design and tuning. Only way to find out for sure is to use the "buy it and try it" method, if it pinks the fuel is not suitable.

Rod

[Carl 3]

Does anyone know how our current fuel quality compares to europe, ie, is our 96 better than the UK 92, is our 98 better than their 95???

[Carl 3]

¿Can someone confirm if Mobil synergy 8000 is the same fuel as BP ultimate, it must be surely?

[Guest Andrew]

same grade of fuel - not same fuel.

[petone 0]

Normally its refinded at marsden point or wherever and then each company adds its own additives. So similar but not the same.

[Jazzbass 1]

Bp claims their Ultimate is made in Oz - how bad is that - it could be Holden-tainted!!

8. Where is the petrol made?

Ultimate is sourced at BP's refinery in Perth, Western Australia and shipped to New Zealand.

BP NZ

[rxsumo 33]

I've scribed this up elsewhere but.....

In the past there have been 2 major sources of gas, for NZ Marsden Point and BP's Western Australian plant.

With the exception of Auckland which gets piped gas, the general rule was if your local port was big enough to take off shore tankers you got Aussie gas, if you could only accept coastal tankers you got NZ gas.

Of late with things tightening up, it would seem that we are getting more gas imported from Singapore.

BP Ultimate arrives in NZ as 98, which is why originally it was available in a few spots as it was Aussie gas, I'm guessing that the Ultimate "Blue" might be brewed here. Mobil's 8000 is regular premium gas with additional additives.

The MON count is the pinking counter.

We had my Si down south a couple of years back and our first dose of South Island Coastal gas was from Twizel, the car pinked constantly and by the time we reached Invercargill it was time for Octane Booster as the pinking was driving me nuts.....2 bottles of Octane booster later and things didnt get any better.

I rang Shell to bitch about their fuel quality, and ended up speaking to a guy that had spoken to us at car club, and he explained the problem.

Apparently the specification for NZ gas says that you can have up to 10 points difference between the RON and MON counts, the high compression motor in the Si wants a MON count of around 88 or better, the NZ gas at Twizel and through the lower part of the Si at the time was more like 86...hence the rattling motor.

The other consideration between 91 and premium , is the physical weight of the fuel. One of the reasons that 91 may ran like crap in your late model FI cars, is that the density of the fuel is weighted for use in carburettors. Premium gas is lighter designed to flow better throughhigh pressure injectors.

The engineer at Shell, who spoke to the club, when the unleaded gas was introduced, reckon the biggest issue facing the use of unleaded gas in older engines was working out timing and spark plug requirements, as the burn characteristics changed with the fuel density.

and we havent even got onto winter and summer fuels.......

[Carl 3]

I should chat to you over a drink, so your recommendation is?

[kiwi535 538]

and we havent even got onto winter and summer fuels.......

waits for ethanol blends with trepidation

I should chat to you over a drink,

I am in!

[Carl 3]

Yes, given that we export 10 million litres of pure ethanol a year, why don't we put just a couple more % of it into our gas...it's bloody good stuff and makes for interesting syphoning sessions - which brings to mind that we've got to be wary about fuel poachers these days, I like the story in the dom the other day about the farmer that spiked his own fuel so that would be thieves wouldn't get very far, the Police comment was "we advise against people taking the law into there own hands" which was stupid considering they were caught red handed.

[rxsumo 33]

Funny you should mention Bio-Fuels......

I was at the MoT's seminar for the upcoming emissions regulations earlier in the week, and the issue of Bio-Fuels came up.

The government passed the specification for up to 10% ethanol in pump gas back in 2002. The issue is that the fuel companies are a little scared of doing it, because they are unsure of the impact to your car, and the possible negative impact on their wallet when you sue them for damages.

The problem is that the manufacturers wont tell anybody what models will happily accept the fuel with no ill affects.......and the vicious cycle begins

I didnt note the stats....(I thought I have a slide somewhere), but I think I heard that using ethanol for blending will make something like a 0.8% difference in our petrol consumption.....one of the other attendees made your point about we have millions of litres of the stuff.....we could lower our petrol usage etc...etc, and then the stats can out a while later....which sorta did the great idea...but not as practical as it seems at the onset...

[Carl 3]

Currently Fonterra sells most of the left over ethanol (10 million litres, more is used for industrial chemicals) dirt cheap to russia for making cheap and nasty vodka...hello???

You'd think with NZ having rather forward thinking people we'd be jumping on the idea.