[jlr_1304]

Most of the premiuim gas here in the MTL region is 91. We do have petro-canada with 94 octane, but it is 6-7 cents more/litres.

would there be a noticeable difference in using a 94 octane fuel over the 91?

[kskpsu]

Originally Posted by Fryguy29

Thanks so much for the link!
Now a question for the entire group. Which is better for the car? Ethanol free 91 octane or 93 octane that contains ethanol? Many of the places that are ethanol free are listed as only having 91 octane. Any thoughts?

No problem. Ethanol free all the way, and you'll get better gas mileage to boot. Took my former 2005 X5 4.8is to Minnesota with the corny Shell 93 from IL, came back strictly with ethanol free gas from MN and WI (91 Shell and Kwik Trip). Conditions were identical each way, but posted 3.5 mpg better with the pure stuff (significant because my baseline was 18.9 mpg). Ethanol's existence is only due to lobbyists, it has no merit...from the energy required to produce it, the increased consumption offsetting the supposed emissions favorability, its negative effect on supply/price for consumable crops, to its downright destructive nature (most significantly to small engines). Go to your local Fleet Farm there in Wisconsin, the farmers benefiting from the financial incentives to grow corn for ethanol (thankfully the subsidy expired) have ethanol free gas at their disposal, they won't use it!

[Radioactive]

You know, almost all the gasoline in the states comes from the same refineries, whether it's Shell or Cheapy Mart. It's only the "additive" added at the end which differentiates the marketing of brands. I don't know if this still is true since I can't find the information quickly, but tests a few years back showed Union 76 as the top performance fuel and Shell towards the bottom. For years Union 76 refined their own fuel and here in SoCal it was the choice of any street racer or high performance vehicle owner.

[kskpsu]

BMW advocates for top tier gas...here is a source for who qualifies:

http://www.toptiergas.com/

Detergency has diminished relevance in direct injection engines, since the valves aren't treated to this attribute of fuel as in traditional fuel injection applications. All I need to do is take apart the intake manifold on my RS4 for this friendly reminder, the notorious carbon deposits are the Achillies heel of its otherwise amazing engine.

[Le Chef]

Can't see why you would use a lower grade of fuel than recommended in the handbook.

[gareth12468]

Originally Posted by jlr_1304

Most of the premiuim gas here in the MTL region is 91. We do have petro-canada with 94 octane, but it is 6-7 cents more/litres.

would there be a noticeable difference in using a 94 octane fuel over the 91?

I have tried both and cannot tell any different between the two.....

[Nahoa]

Originally Posted by kskpsu

No problem. Ethanol free all the way, and you'll get better gas mileage to boot. Took my former 2005 X5 4.8is to Minnesota with the corny Shell 93 from IL, came back strictly with ethanol free gas from MN and WI (91 Shell and Kwik Trip). Conditions were identical each way, but posted 3.5 mpg better with the pure stuff (significant because my baseline was 18.9 mpg). Ethanol's existence is only due to lobbyists, it has no merit...from the energy required to produce it, the increased consumption offsetting the supposed emissions favorability, its negative effect on supply/price for consumable crops, to its downright destructive nature (most significantly to small engines).

+1

[flash3]

BP premium 93

Been filling BP in all my cars - no other gas goes into my cars

[lbjgh]

donno is the manual helps?

[jsbos]

Interesting that BMW recommends one brand. Wonder if BP paid for that endorsement?

I've seen other "top tier" lists that include Shell and Texaco but not Mobile.

[colson79]

Originally Posted by jsbos

Interesting that BMW recommends one brand. Wonder if BP paid for that endorsement?

I've seen other "top tier" lists that include Shell and Texaco but not Mobile.

That's because it cost money for the Fuel vendors to be part of the Top Tier program. The license only last two years so vendors on the list are always changing. The interesting thing is that BMW is one of the automotive manufactures in the Top Tier group but my owners manual states BMW recommends BP which isn't currently on the Top Tier list.

I personally only use premium fuel and prefer ethanol free gas. BP in my area doesn't offer ethanol free gas so I usually get Kwik Trip or Shell.

[mibmwx3]

Originally Posted by jsbos

Interesting that BMW recommends one brand. Wonder if BP paid for that endorsement?

I've seen other "top tier" lists that include Shell and Texaco but not Mobile.

Mobil is listed on the "top tier" list. It's Exxon.

[walendvay]

87. ran it in my '2004 E83 with no issues. I am at elevation, as there is an atmospheric pressure associated with the flashpoint of fuel.