Use of differant petrol grades

nzeder · Post by **nzeder** » Mon Jun 27, 2011 10:28 pm

What we need is high Octane fuel like in Japan aka 100 and have that available throughout the country.....hang on I must be dreaming that will never happen.

djz · Post by **djz** » Mon Jun 27, 2011 10:35 pm

Pretty sure that info is on their website. I managed to drive from Christchurch to Auckland and never had a problem finding BP's with 98. I guess if you were going off the beaten track it might get a bit trickier.

Buster · Post by **Buster** » Tue Jun 28, 2011 12:15 am

You used to be able to print a simple list of the BP Stations selling Ultimate 98 off their website.

Alas they have flashed up their site and it's not that simple anymore.

At a quick count of Ultimate 98 Stations on their map it looks like about 20 in the South Island and 75 in the North Island.

None north of Orewa, and none in Coromandel.

I guess the smart thing is if you know at the start that you will need a little top up of 95 to get to the next BP Ultimate then put it in sooner rather than later (when the tank is still 3/4 full say) as the octane dilution will be less.

beta · Post by **beta** » Tue Jun 28, 2011 6:28 am

I used to live in Dannevirke and they brought in 98. Ended up going back to 95 because "the demand wasn't there". There are 3 BP's in Palmy, only one sell 98 is on Rangitiki.

old_datto_fan · Post by **old_datto_fan** » Tue Jun 28, 2011 7:42 am

There is no BP or Mobil 98 in Taranaki either. I have found some Gull stations though that have 98 and is not the Biofuel stuff although their web site says the only 98 is Biofuel so I'm not sure what the deal is there.

Buster · Post by **Buster** » Tue Jun 28, 2011 4:12 pm

'BP 2go Powderham' is showing on the BP site as selling 98. Right in New Plymouth. Maybe it's wrong.
We have a daughter in South Taranaki so top up the Skyline with 98 at Te Kuiti on the way down and get back to Hamilton no problems.

In Palmerston North they show two. Rangitikei and also Fitzherbert.

Actually BP Connect in Dannevirke is also listed as selling 98. Sounds like this is wrong as well.

Brock365 · Post by **Brock365** » Thu Jun 30, 2011 5:59 pm

Just filled up with it. Due to BP up the road having 98 and mobil up the road not I have not tried Mobils 98 before. Will see how it compares

Jibber · Post by **Jibber** » Fri Jul 01, 2011 6:16 pm

I can't vouch for Mobil, but I know the BP website has a map where you can find which stations have 98. Pretty much all the Wild Beans seem to be the way to go.

My Z32 mainly runs on 95 I must admit. I've run on BP and Mobil 98 and not really noticed a difference over 95. That said I used to have an A32 Cefiro and the difference between 91 and 95 was noticeable passing, and I could tell the difference between 95 and 98 as well. That was back when 98 first came into NZ, last century...

Since then, I had a Cefiro Wagon, which ran exclusively on a diet of 98 except when it wasn't available and I was caught - in the far north of NZ or similar. Wasn't as noticeable a difference, but one of my staff once filled it with 91 and it wouldn't pull the skin of a rice pudding.

My experience has been that age and compression level will push you towards higher octane fuels - my cefiros had fairly high compression engines, and my later A33 was even less happy with 91. My Z never goes near 91.

As far as touring goes, if you're really worried about it, keep an eye out for the 98 equipped stations and top off as appropriate. I've found travelling for work that with a range of 450 - 600k, I almost never needed to use 95. Most reasonable sized places these days have a Wild Bean - we even have one in Waihi!

My 2c worth anyway. I'd doubt that running the odd bit of 95 will do any real damage - keep your boot out of it and I'd think you'd be fine

Pilot.P · Post by **Pilot.P** » Fri Jul 01, 2011 9:32 pm

Thing is a higher octane fuel tends to have a lower calorific 'heating' value. For a high compression or forced induction engine, the benefits from the anti knocking properties of a high octane fuel normally outweighs the lower energy content. In saying that some engines will run 'better' with a lower octane rating fuel simply because there is more energy per mass of fuel. From my experience most modern n/a engines run better on 95 than 98.

Oh yeah, there's definitely two BP stations with 98 in Palmy

ZMAD · Post by **ZMAD** » Fri Jul 01, 2011 11:42 pm

Yeah,dont knock the 95. have run on that for many years.

Brock365 · Post by **Brock365** » Thu Jul 07, 2011 3:34 pm

It feels like the BP 98 had more GO. Dont know why that would be. Run my 280ZX on BP 98 and made me think.

Im old enough to remember we HAD LEADED super petrol, but not old enough to have made much use of it. Given the age of some Z cars, did they prefer the old leaded petrol? And what octane was Super?

Jibber · Post by **Jibber** » Thu Jul 07, 2011 7:41 pm

It was 96 in those days, back when you could judge the state of tune by the colour of your tailpipe. Leaded fuels burnt white.

Go back even further and we had 89 octane leaded - regular before we had regular 91 unleaded. Maybe early 80's, late 70;s?

Do older Z's need lead replacement?

Buster · Post by **Buster** » Thu Jul 07, 2011 7:57 pm

Everything that came from the factory with a catalytic converter takes unleaded.

sogy trype · Post by **sogy trype** » Thu Jul 14, 2011 10:06 am

Keep in mind when doing a cost analisis the compresion ratio and advance degrers.98 octain works ok up to about 8.9:1 comp with around 2deg advance.The fuel burns very fast hence the 2deg.If you want economy with power put 20 persent avo fuel in the low octain and the lead in it slows the burn rate and you can crank your advance up a bit more.You needs throw leagality out the window also.Its a fine line to juggle all these factors.I find it easyest to run low octaine with very little advance during the year and running a bit of avo fuel and some advance on the road trips.