Shell's New Optimax Extreme

[wrx365]

Originally Posted by buickman

I've tried BP ult & have found no difference to Shell's Optimax Mobils Syn or Uniteds Boost 98 on running or performance in A VCT pwrd AU.
But my nephew has a 2000 WRX that has had a lot of engine mods & when his filled up with BP ultimate the car losses performance & will only run to its best on Mobils synegy or Shells optimax. Speaking to him his still not sure about using ethernol in his car even at 100 Octane

Even though all the high octane fuels are rated 98RON, each are refined differently. Shell OPtimax and Vortex 98 both are refined using aromatic compounds to increase their Octane rating, whilst BP Ultimate used a different method to achieve their 98 Octane rating. The advantage for BP it produces a much cleaner fuel, compliant with new Euro III emission laws, however it is a lesser denser fuel than Optimax, Vortex 98 and Mobil Synergy 98. And as we know the denser the fuel the more power it can help produce.

In standard tuned cars you should notice little or marginal difference between the 98 Octane fuels. There are come cars have with smart ECUs like the WRX that can adjust settings depending on the fuel being used.

However with modified cars you should continue to use the same density type fuel the car was tuned in. It sounds like with your nephews car it was tuned with Optimax and BP Ultimate.

[sfr rob]

i swear today, filling up i read.. DO NOT USE IN AIRCRAFT.. i looked twice, and i SWEAR thats what i read... WTF??

[Redrum]

I still laugh when they use Dick Johnson to try and push this stuff. He is so independent from shell!!!

[ricthewheelie]

Originally Posted by GT595

God only knows the reasoning behind the no optimax policy in WA - BP must have friends in high places......

It to do with the additive in fuels over East called MTBE which can poison ground water supplies which makes up about 40% of our drinking water

[russellw]

The E10 blends (10% Ethanol) have been supported for use by all four of the major players in this country - Ford, Holden, Mitsubishi and Toyota for vehicles manufactured after 1986. A small increase in actual consumption is likely given the fuel is not as dense and has a lower calorific value.

CO emmisions are reduced by 32% and HC by 12% and the fuel is considered to be greenhouse neutral.

The E5 blends like Boost 98 are probably likely to gain better initial acceptance at the consumer level especially as there is a price discount to "normal" 98 octane fuel.

The concerns with blends above 10 % relate primarily to the water absorption properties of Ethanol which is why it is not recommended for use in marine applications - aircraft are a similar issue with the main concern being seperation of water and fuel within the tank and difficulty in maintaining adequate mixtures at altitude.

Cheers
Russ

[Stav]

Ive had some in my tank since yesterday and my dte is dismal.I think this fuel supports performance but not mileage.

[FTE217]

Originally Posted by useless

Ive had some in my tank since yesterday and my dte is dismal.I think this fuel supports performance but not mileage.

I have run 2 tank fulls this week, throttle response is better imo but it definately burns faster.
I did Sydney to Newcastle and running around there for the day and back to Syd last night.
DTE was at least 100k's less than 98octane. I don't bother about how many litres otherwise I wouldn't own a fuel drinker ! :sm_headba