my530i

I remember 8 years back or so, there was 93 octance at an Exxon gas station. Then I the best I could find is 92. Now I can only find 91 in Northern California. If anyone know any gas station supply anything above 91 octane, please let me know.

Rudy

Sunoco has 94 octane here in Pennsylvania...

BP/Amoco has a 93 octane.

I'm surprised that you only have 91 in California!

CRRobert

I have seen a few places that sell the Sunoco 100, but it is pretty much considered race gas AFAIK. I have had 104 for my dirt bike. A great race gas smell when burned with castor oil.

Another place to maybe check, is Boat Marina's. They were selling 93.5(normally 91 is hightest) in the vicinity for some of the high powered boats, even in Denver.

Guest

I have not seen any gasoline with higher than 91 octane (US) in SoCal. Even the Shell V Power stuff is 91. I have seen V-Power at 93 octane (US) in Texas and Louisiana.

The lower octane rating in CA may be due to the special emission control formulations of gasoline that are mandated by CA regulations. If necessary, there are probably aromatic (benzenes, etc.)/other high carbon number gasoline additives available that can be used to raise the octane number. As explained earlier, this would not necessarily improve the HP or engine performance since the ECU has to be remapped to take advantage of the higher octane rated gasoline.

chicosy

Could this lower US octane rating (91) which is equvalent to Europe's RON 95 be a cause for why so many people are complaining of low response to their engine or throttle? The cars are deisgned to run RON98 everyday so putting anything less than that would compromise engine performance right?

I mean, it's ok for them to use it but they won't get the same performance as a guy who's running RON98 fuel. Please tell me if I get this right or wrong.

kigerka

I use US 93 which is 98.

According to my gas cap it says in English to Use 91 so I would say that it is safe to use US 91.

JDN

I hope so. I am beginning to drift from 93 to 91. Gas cap says a minimum of 91, but also says premium. In most of the SE US, premium is 93.

Iceman

On the 545 I would ALLWAYS use the highest available, but no racing gas.
Why do you want to use the minimum???

JDN

$$$

Iceman

But downgrading means you get less MPG. The difference between 91 and 93 isn't that bad, so you will not safe a lot, maybe a couple cents per month...
I don't think it safes you money!!!
All I can tell you is, I use the German 100 octane and I am very satisfied!
It also seems to give me more mpg!!
I wouldn't downgrade from US 93 oct to US 91 octane, unless the price difference would be HUGE...