Hi All,

This very helpfull group recently helped me with the issue of a gas station selling me 87 octane at a 91 octane pump. Adding some octane from a bottle and then filling up with premium (from a different gas station of course) fixed my lazy performance and it seems even better than it usually is.

Here is my question: My dealership told me that the 2.7T engine uses 94 octane gas in europe. All the 94 octane available where I live has freaking corn (ethanol) added which my dealership told me is a BIG NO NO for Audi engines.

Has anyone tried adding a bottle of octane to a 91 octane fill up to get a 94 octane number? If so, how did it effect performance? I'm asking because right now I am about at a 92 octane level due to the added octane with premium gas fill up and my performance is great and the turbos sound louder, emitting a wicked WHOOSH sound I never heard at this volume before.

Im thinking of trying a bottle of octane with my next 91 octane fill up. Thoughts?

 

I did some searching on the web. Not much out there specific to your question, but there is some conversation here: http://www.audizine.com/forum/showthread.php?t=103841

I know that I can't justify or afford to be the guinea pig, but good luck with that

 

well, I'm not too into being a guinea pig either I decided to ask my dealership. I'm in Calgary, pretty freaking high altitude. Higher you are, less octane I heard. But its running so nice right now with the added octane. Most resources I have seen say the 2.7T should use 91 octane but mine is an S-Line (same as yours trdltly) chipped to 280 ft pounds of torque at 1800 and 15 more horses than the normal 2.7T. It really seems to like the added octane. I'll see what the dealership says and let you know...I have a 2 year warrenty with them and I am sure they will want to protect it and give me an honest answer.

 

Frizzle,

Chances are that the dealership, really, won't be able to tell you anything. They simply don't know.

I don't THINK that Audi says added ethanol is taboo. They DO sell them over here, and if they said you would have to search for the 1 in 100 stations that carry non-ethanol added fuel, you might decide to buy a car that it is not taboo.

Do a search on octane boosters. I think I have read that they do not anywhere near boost as much as they claim, and it is definitely not economical.

Better you find a station you can trust. My local Sunoco has 6 cent discount on a different grade each day, for 3 days of the week. I buy 93 on Wednesdays for about 12 cents more than that day's Regular. I agree, the car, in my case, '97 2.8, likes the 93 better than the 87 or 89.

17 gals or so, that 12 cents is about 2 bucks a fill up. So I buy it.

Cheers,

George

 

Calgary is at 1200m altitude above the see level, cold and dry.
Due to difference in the octane rating measurements = in N.A the posted octane rating is ~4 points less than the equivalent rating in Europe.

(be aware that if one uses higher octane rating than the engine could take - unburnt hydrocarbons in the exhaust gases are present-efficiency suffers, pollutions are high, carbon deposits appear.
For best gas qualification - use a gas analysator (in your exhaust) to read the output content)

Ask your dealership what are the octane requirements in India!

 

So the dealership says that there is not much point in adding octane booster to premium fuel for the A6 2.7T. They did say that it may be a good idea to keep a bottle in my trunk in case I have to fill up and there is no Shell station around or no premium available. From what they said and from what I have read, Shell V-Power is THE gasoline to get. Stick to V-Power and I should never really notice much of an improvement by adding octane.

 

Speaking a little out of ignorance here, but I thought octane boosters contained lead....which is a no-no for catalytic converters. Other than that my advice is to stick to premium if you really think it makes a difference, and avoid the additives. I usually use midrange (89 octane at 900' above sea level) and occasionally premium (91), and notice little difference in acceleration or mileage. Certainly no difference in engine sound.

Ethanol of 10% or less should not hurt the vehicle, but I avoid it since it seems to generate less mpg in spite of the higher octane and I worry that the ethanol could ruin rubber and seals since it is more caustic than gasoline.

You might ask the dealer if you are covered under warranty using 10% ethanol based fuel.

 

I don't think ethanol will void the warrenty, but the dealer did emphasize that ethanol should be avoided. I'm pretty sure the words they used was "Keep that crap out of your engine"

 

Every station I have ever used has 93 octane. Some have 94 (sunoco). I have the 04 s-line and it runs wicked with the 93. Thats all ive ever fed it. 91 is the highest you can find?

 

I can find 94 no problem. Except that its got ethanol in it. My dealership recommended I go with Shell V-Power 91 rather than 94 w/ethanol. It was my understanding that all the 94 rated fuel in north america has ethanol in it. Thats certainly the case where I live.