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Hey just wondering if any one could tell me if optimax is 96 or 98 octane. I normally fill up at BP on 98 octane (premium) but filled up on optimax today.. Since filling up on the stuff my car has lost all power and feels like it did before installation of my new pump (slow as crap, no power at boost, farting etc).. This has all co-incided with my alternator/battery getting consistently worse, and i was just wondering if the optimax was 96 octane, because that would probably make more sense, than my battery/alternator getting worse so fast

thx

Edited by r32 gts-turbo
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hi

Ive always sworn by BPultimate & optimax but just last week i got about 50kms more out of a tank using Mobil petrol(synergy). I only used it by chance but it worked out better. the performance improved aswell & i was using the power a little more, compared to with the other fuels.

My friend had the same situation with his 05wrx, he agreed. i have a r34 and ill be using Mobil more regularly now.

cheers

steve

hi

Ive always sworn by BPultimate & optimax but just last week i got about 50kms more out of a tank using Mobil petrol(synergy). I only used it by chance but it worked out better. the performance improved aswell & i was using the power a little more, compared to with the other fuels.

My friend had the same situation with his 05wrx, he agreed. i have a r34 and ill be using Mobil more regularly now.

cheers

steve

I hear the synergy is better then ultimate or optimax. I wish we had it in QLD. I always used bp, as their fuel is refined to 98 ron while optimax ( from what I have been told) has sh*t added in to bring it up to 98 ron

I was under the impression that Optimax was actually 99RON. I remember reading something about it a while back, it is the highest octane fuel available (until they released Extreme - 100RON).

Also, the V8 Supercars use Optimax, so it can't be that bad, I have used all 4 types of Hi-Octane Premium, and I am buggered if I can tell the difference.

Yeh sorry meant ultimate not premium. Filled up with ultimate today and its better. Doesn't stutter anymore and pulls harder on boost (althought not as hard as it did before putting optm.. weird..) Probably some rooted fuel related sensoor somewhere doesnt like the optimax and makes my car frig up or something. Ill try the mobil tomorrow and post back if i notice any difference

Edited by r32 gts-turbo

Shell Optimax 98

Shell Optimax Extreme 100

Mobil Synergy 8000 98

BP Ultimate 98

United Boost 98 Umm 98 maybe

Some cars dont like to be run on Optimax due to the additives that are in the fuel, detergents etc can foul the plugs (heard of it being more common on motorbikes) My old car used to get the occassional miss and get 50 kms less to a tank when i used the Optimax

And with the new car, i use BP Ultimate and Mobil 8000, never had any dramas with either of these.

This subject has been discussed so many times in so many threads. I am not going to tell the whole story again, if you want more than this post do a post search, "Sydneykid" and "refinery".

Oil companies have a policy called "refinery sharing/exchange" because it is simply not economical for each oil company to have a fully equiped refinery in each state. Refineries need volume to make money, it's that simple. Do a Google search on "oil refinery sharing", you will find ALL oil companies in Australia refinery share.

For example, there is NO BP REFINERY IN MELBOURNE, so do you think they ship it in, millions of litres per week in tankers from WA or Qld? Like hell, they refinery share and buy (swap) the fuel from a local refinery. If you want to know what refineries are in Melbourne (don't forget Geelong) look it up in your yellow pages. When you buy fuel at a BP servo, chances are you will be pumping fuel from one of those refineries not a BP refinery.

A quote from the BP Australia web site tell it all....

"A particular feature of the Australian oil industry is the practice of refinery exchange, in which refining companies exchange products in various locations to minimise distribution costs. For example, BP supplies other companies in Perth and Brisbane and in return is supplied with product in Melbourne, Sydney and Tasmania."

:D cheers :P

Edited by Sydneykid
Hey just wondering if any one could tell me if optimax is 96 or 98 octane. I normally fill up at BP on 98 octane (premium) but filled up on optimax today.. Since filling up on the stuff my car has lost all power and feels like it did before installation of my new pump (slow as crap, no power at boost, farting etc).. This has all co-incided with my alternator/battery getting consistently worse, and i was just wondering if the optimax was 96 octane, because that would probably make more sense, than my battery/alternator getting worse so fast

thx

no, it doesn't make more sense. your rough running problems are much more likely (ie 99.99999999%) to be caused by your charging problem resulting in poor/weak spark. This would be especially noticeable under load/boost or at night (ie when your lights are on).

Edited by hrd-hr30

most of the "perceived" differences in 98 octane fuels are usually just in your head. I have a friend who works for shell, who says all the 98 octane fuel is exactly the same, (actually not technically true, i think the united boost uses ethanol in their fuel)

though, i do have a couple of friends who call optimax "opti-ping"....

i generally use either optimax or bp ultimate, and i don't notice any difference at all

I fill up with BP when I don't have a 4c discount docket, but when I do, I fill up at Shell. So my 32 is pretty much 50/50 on Ultimate and Optimax and tbh I notice no difference swapping fuels.

And from what Sydneykid said, it's probably because it's all the same anyway!

ive heard all the fuel myths and dont believe any of them myself.

ive heard more than 50ks difference on a given brand xyz fuel rating (sounds like driver habits if anything).

ive heard more or less engine and performance between 98 rated brands and so on. ive always used optimax and never had problems. ive tried the other brands as a bit of humour to try out some rumour and it all feels the same.

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