I know this is slightly off topic, but am curious to know what others think...

Shell Australia has just introduced a new premium petrol called Shell Extreme - they advertise it as 100 octane fuel but add the point that it's 5% ethanol - www.shell.com.au/extreme

I've always filled up with 98 octane fuel and when I heard about the 100 octane I was curious. However, now that I now it has the 5% ethanol, I'm hesitant to use it.

Anyone got any thoughts or experiences with this? Apologies for being slightly off topic.

 

IMO I think your car will not only perform better but the engine will probably last longer when you burn cleaner gas. The way I look at it I'm sure the gasoline companies mix other crap in the gas to get more profit per gallon. So why take a chance with your expensive toy. Just feed the best gas you can get and enjoy it.

 

I would go with what the manufacturer says is OK--after all the manufacturer may have a reason for its recommendation. I don't remember what my manual says. But, IMO, manufacturers like to say that their cars don't have to use the highest octane when true. So, if BMW advises one to use only premium, then that is what I would do. Will it likely make a noticeable difference to the average first owner? the average second owner? Probably not--except in the pocketbook and in the HP--two effects that would be scarely noticeable to all but the HP guys and those who drive many miles.

 

This has been covered here http://forums.e60.net/index.php?showtopic=20162

 

Something else to consider is the brand of gasoline. BMW and other auto makers have developed standards for gasoline composition to control deposits. More info is here:

http://toptiergas.com/

In the long run, using gasoline other what is recommended may
deterioriate engine performance. For those that lease, it may not be their problem. For those that buy these cars, they may have a problem.
Another reason to stick with new cars, perhaps.

 

This topic has been brought up many times over the years on just about all of the BMW sites and it all comes down to what ever you are content in doing.Do what the manual tells you about using minimum octane rating 91,(page 169),or use a lower octane and take your chances its your choice to make.IMO after paying $50,000+ for a car its just not worth it to me to save $100.00+ a year on the lower octane. You spend more than that on a night on the town.Good luck
cheers
vern

 

I have used different grades of fuel here (RON95 and 98; think it's 89 and 91 in the US). The car ran fine but in our stop and go driving conditions here, I have noticed the cost/distance ended up about the same. Well, maybe the higher grade is S$0.01 (==US$0.01/1.7) more expensive for every km. And, there is a slight loss of power with the lower grade.

But I never did proper tracking; just some mental calculations as I went along. But I don't think I am too far off... I can probably go to a very nice restaurant once every year with the saving. Instead, I feed them to the car.

 

I've used in my 525i, 89, 91 and 93 with never any problems, As the norm, I stick to 91 but occassionally go with 93. I guess its a user's preference.

 

For example the 530i is said to have 255 hp in the US where the ocatane is not higher than 93,
in Europe the same engine specs gives 258 hp with 98 octane gas.

Higher octane = more hp and better milage.

The BMW engines are made to use higher octane but they work great with lower as well.

 

Sorry but no. Read my earlier posts. The octane measure in the US and the EU are different. Comparing the two would be like saying that the US E60's only hold 18 units (Gallons) of fuel while the EU E60's hold 70 units (Liters). The different in horsepower also has to do with changes in measure. A HP is not the same on both sides of the pond. The information on the HP measurement is also in an ealier post but I think the difference is small 1 hp=1.014 hp. So HP output is the same it's just the units of measurement are not.

Like to other posts...

http://forums.e60.net/index.php?showtopic=20162&st=0

I think your message is right in that lower octane will give you a little less power but for different reasons. And putting in higher octane than what the car was designed for will NOT give you any more power.