It has been planned for New Zealand to have 95 octane fuel since the lead was removed from New Zealand’s fuel in 1996. At the same time as introducing the unleaded petrol specification in 1996, Government also changed the specification for premium fuel to the international specification of 95 octane.

Unleaded Premium was introduced as a 96 octane fuel in order to help older vehicles designed to use a premium leaded fuel that were, at that time, still present in New Zealand in significant numbers. It was always anticipated that octane levels in unleaded premium would be reduced to the regulated limit of 95 octane in due course.

With the Government’s changes to fuel specifications that took effect on 1 January 2006, it is more difficult and expensive for the New Zealand Refining Company and overseas refineries that supply New Zealand to continue producing 96 octane fuel.

Now is the right time to introduce 95 octane fuel, with the rest of the Government’s new fuel specifications, as has been planned for nearly 10 years.

What is required by law?

95 octane is the minimum octane required for premium fuel under New Zealand law. The New Zealand Refining Company will continue to produce, and BP will continue to sell fuels which meet the Government’s requirements.

Does 95 octane cost more or less?

The pricing of fuel is for the individual fuel retailing companies to decide. BP cannot comment at all on what other companies may or not do.

However, with the Government’s move to lower benzene petrol, continuing to produce 96 octane in New Zealand would have led to increased production costs as more petrol components would have to have been imported to allow its continued production.

The new Government fuel specifications which the New Zealand Refining Company began to produce to from 1 September 2005 lower the benzene content in petrol. This made it more difficult and expensive to continue producing 96 octane fuel.

Reducing the octane for premium petrol to 95 helped to offset these additional production costs. Continuing to produce 96 octane petrol would have resulted in a more expensive product.

When did the shift to 95 happen?

Moving to 95 octane fuel required a great deal of work in terms of changing branding and marketing at service stations. This shift o occurred from October to November 2005.

What is the international standard?

The international standard premium is a 95 octane grade – this is the grade most commonly used in Europe and is the normal premium grade in Australia. The Government’s fuel specification requirement also lowers the allowed content of sulphur in diesel and benzene in petrol to international standards.

Producing 95 octane fuel further brings New Zealand’s petrol's into line with international standards.

What about imports?

New Zealand imports around 40 per cent of its finished petrol, with the New Zealand Refining Company producing the other half.

The move to the international standard of 95 octane makes it easier for New Zealand to source suitable petrol for import into New Zealand increasing the security of our petrol supply.

Where do we import our petrol from?

BP sources most of its imported petrol from Australia, and the rest from other Asia-Pacific refineries.

What countries continue to sell 96 octane?

96 octane fuel is becoming increasingly rare. A few countries continue to use leaded 96 which New Zealand stopped using in 1996.

What are the benefits of 95 octane fuel?

95 octane fuel is easier to produce than 96 and can have a drive ability benefit for the motorist. Because the octane is lower, the composition of the fuel can change towards slightly lower aromatics.

Aromatics are high octane components but have low volatility, so reducing aromatic levels can result in improved drive ability, i.e. easier starting and less hesitation under acceleration.

What are the other companies selling?

BP cannot comment on what other companies may or may not be selling. All we can say is that the New Zealand Refining Company started production of 95 octane petrol late 2005 and BP started selling and marketing 95 octane premium fuel from that date onwards.

It is important to note that for people wanting a higher octane fuel, BP offers its premium 98 unleaded BP Ultimate at over 100 of its service stations across the country.

Is there be any change to Regular?

Yes. The new one per cent benzene limit applies to Regular as well as Premium and sulphur in Regular has also come down from 350 to 150 ppm. The octane remains at 91.

What has sulphur and benzene got to do with octane?

Sulphur can be reduced without any effect on octane, but benzene cannot. This is because benzene has a high octane number. Reducing benzene from three to one per cent, as the Government’s new fuel specifications do, affects the gasoline octane pool, or the total amount of octane available for the Refinery to use.

Overseas refineries are affected as well because there has been a move in several Asia-Pacific countries, including Australia, to reduce benzene levels in fuel at the same time as New Zealand.

Why has benzene been added to petrol when it is a carcinogen?

Benzene has not been deliberately added to petrol for many years. Benzene occurs naturally in crude oil and may be introduced as a by-product of refining processes designed to improve octane. It is difficult and expensive to separate and remove benzene, but this is one of the two main purposes of the $180 million Future Fuels at the New Zealand Refining Company, which produces these new fuels.

How will 95 affect my vehicle?

Most cars that have used premium unleaded 96 will run just as well on premium unleaded 95. A few will show an increased tendency to ‘knock’ or ‘pink’. These are likely to be mainly pre-1990 European or Australian cars.

What is ‘knock’?

‘Knock’ occurs when pockets of petrol vapour in the engine burn roughly, causing stress to the engine.

There are two sorts of knock. Knock at low engine speeds is called ‘pinking’ or ‘pinging’ and can be detected by a high pitched jingling sound inside the engine. Knock at lower engine speeds generally doesn't cause much harm.

Knock at high engine speeds can’t be detected easily but can cause serious stress to engines.

How can engines avoid knocking?

There are several ways to do this depending on the type of car:

Ask your mechanic to check the ignition and fueling system of your car for faults, and then re-tune the engine for best performance and economy if this is possible. This should be carried out regularly anyway and can usually be done at a moderate cost.
Use a higher octane fuel. If you use 91 octane now, switch to 95. If you have been using 96 octane, try using BP Ultimate if it is available in your area.
If your car is an older model, eg was manufactured before 1986, it could have a build up of carbon deposits inside the engine. Older cars with cast iron heads, especially British and Australian models, need to be decarbonised (decoked) about once every 10 years or so. Your mechanic or re-conditioning workshop will need to remove the head, so it is an opportunity to have your engine inspected and other work done on the engine at the same time.

Note: Modern engines with high compression ratios, eg post 1995 European models are usually fitted with knock sensors. Once the sensor detects that the engine is knocking, the engine management system can adjust the timing of the engine and stop pinking from occurring.

What is octane?

Octane is a measure of a fuel’s resistance to ‘knock’. Low octane fuels can result in some cars pinking at low speeds or when hill climbing, especially on hot days.

The octane scale is a 0 to 100 scale but, generally, a petrol engine won’t run on a fuel with an octane value below about 70. By today’s standards, 85 is a low octane fuel and 98 a high octane fuel.

Do all cars see octane the same way?

No. Cars with high compression ratios, eg 10:1 need a higher octane fuel than cars with low compression ratios, e.g. 8:1. The higher the compression ratio, the better the performance of the engine, but the greater the need for a high octane fuel in order to avoid knock. (Having said this, some engine manufacturers have found ways to get quite a good performance from lower octane fuels.)

What vehicles may be affected?

Most cars that used a 96 octane fuel will experience little or no change from shifting to 95 octane fuel. This is because most cars made from about 1990 onwards have been designed to use either a 91 unleaded fuel (Japan and Australia) or a 95 unleaded fuel (Europe).

A small number of pre-1990 European cars may not run as well on a 95 octane fuel. These vehicles make up less than one per cent of all licensed petrol-driven cars in New Zealand. A further 1.0 to 1.5 per cent of mainly European cars will need an ignition timing adjustment.

A third group of pre-1990 high performance turbo-charged cars (European and Japanese) may be affected. Most modern turbo-charged cars prefer a high octane fuel but can run on a 95 octane fuel, perhaps with some loss of performance.

What will happen to these cars if they are not re-tuned?

In most cases, audible ‘pinking’ doesn’t cause engine damage. For cars that ‘pink’ at low speeds, it is important to avoid prolonged running at high speeds and under high loads. It is unlikely that production cars will suffer engine stress if the driver is gentle on the accelerator pedal and always drives within normal speed limits.

What about classic cars?

It should be noted that cars designed to run on a high octane fuel will not suffer damage or stress if driven at moderate speeds and under moderate loads. For this reason, vintage or classic car owners need not be concerned. An anti-valve seat recession additive should continue to be used where appropriate.

It is worth noting that older (pre-1965) classic and vintage cars were designed to run on very low octane fuels.

To find out if your car is affected, there is a booklet, the Autodata Unleaded Petrol Information Manual, which has this information on most pre-1990 European cars including Japanese cars sold in Europe.

BP’s Technical Helpline can offer detailed advice. For other makes and models, contact the BP Technical Helpline on 0800 800940 option 5 for general advice and guidance.
If your car begins to show signs of pinking in normal use then you should consult your local workshop for advice.

What should I do if my vehicle is running worse on 95 octane fuel, and can I get a higher octane fuel?

Talk to your mechanic in the first instance who can advise on making a timing adjustment to your engine, or consider using a higher octane fuel.

If you wish to run your vehicle on a higher octane fuel, BP offers a 98 octane fuel – BP Ultimate – at over 100 of our service stations across the country. This fuel is imported by BP and is designed for motorists who want to get the best out of their car. It will more than compensate for the one per cent drop in octane from 96 to 95.

This fuel does cost slightly more than 95 octane fuel as it is an imported high octane product. For more information on BP Ultimate visit the website below.

To see where BP Ultimate is available visit the BP Ultimate website (below) and use the service station finder.

BP Ulimate website

Why has it taken so long to deliver 95?

95 premium unleaded could have been introduced to replace the 96 grade any time from 2002, perhaps earlier. Government changes to the regulated fuels specifications on 1 January 2006 have made now the right time to make this shift.

If higher octane fuel is better for cars, why has New Zealand introduced 95?

Provided the fuel has a sufficient octane number to meet a given vehicle’s needs, any further increase in octane won’t normally produce a benefit. Since 95 octane is the international premium grade, most cars manufactured since 1990 do not need an octane above 95 but some, especially turbo-charged cars, will benefit from a higher octane grade.

Please note, the new 95 octane fuel offers slightly easier starting and less hesitation under acceleration than the old 96 grade.

If BP Ultimate is available in your area, you could use it instead and gain the benefit of a high octane fuel combined with smooth acceleration and a cleaner, more efficient engine.

Our New Zealand fuel specification standards are rapidly catching up with the latest European standards.>/br>
In terms of advising the consumer, we have informed the Government and organizations such as the AA, the MTA and the vehicle importers. Workshops have been advised. Information for motorists is available through leaflets at service stations, BP’s website and BP’s Helpdesk.

Independent information on the regulated changes can be obtained from the Ministry of Economic Development website below or on 0508 33 55 33.

Ministry of Economic Development website