In some places in the U.S., high elevation areas, like eastern Idaho, Utah and Wyoming, the stations routinely sell 85 octane due to the higher elevation and lower density air. They also often sell ethanol at the pump as regular fuel. They do this because they can get away with it.

So yeah, run on some 85 octane, which is below the minimum RON + MON / 2 standard for most all cars these days, go down to sea level and yes, it will ping.

 

Well, I think we can assume that my sources were NOT including this extreme example. Interesting to learn, however.

 

I agee with Southboro. I think it can come down to personal preference and the location you reside in! I live in Maryland and I have used 87 Octance in my 00 2.7T and I find the performance was not as good as if I ran a 93 Octane. I have not experienced any pinging. We have a couple places that sell 100 Octane (price is through the roof).

In the summer, I need to run high test simply because of the outside weather. We get very hot and humid. I noticed if I run 87 Octane in the heat of summer, my car is a little more sluggish then if I was to run 93 Octane in the summer. One thing I can tell you is my car loves the fall season, when temperatures drop a little and the air is a little cooler and denser.

In the end for me, I run at least 93 Octane. It gives me piece of mind and I think my car is happier because of it!

OOOO



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I see no reason why anyone would try to asve a few pennies per gallon and put lower grade gas in the tank. You'd save much more money buying generic brand cola instaed of drinking Coke and Pepsi, but very few folks skimp on the things that they like. Our cars like 91+ octane gas, so that is what I give to her (93 here in MA).

 

I've got a fridge full of RC cola. You want to make something of it? :-P

 

RC is the bomb! I rarely drink cola anymore since I am not suposed to have caffine, but I loved RC!

My dring of choice is Vernor's Ginger Ale. Man, that is so good!

My sentra said to use premium, so I did. I'll be using it my my 2.7t as well. I thought it was funny on the sentra forums I was on that the guys would put hundreds if not thousands of dollars in mods in there car to make it faster, but they'd skimp on the gas. It seems to me that you'd want the best performing fuel for a performance car. Especially when you've put a lot of money making an ok car much faster. (the sentra being an ok car)

 

Ever tried Reed's Ginger Beer (non-alcoholic). Available at Whole Foods and Trader Joes. Very strong ginger flavor.

As I said above, I generally put premium in my ride because I want the additional fun factor when I hit the gas. Mid-grade or regular on occasion lately (unemployment will do that to ya). Just don't like to see the spread of modern-myths (no objection to the ancient and/or entertaining). The notion that a tankful of 87 octane is going to hurt your Audi is unfounded.

 

never tried it. my wife did bring me 3 different varieties of ginger beer/ginger ale, and they were too strong for me. Vernor's is perfect for me! Canada Dry sux in comparison!!

 

Any good enginneer will look at all the examples. They wouldnt just exclude the extreme examples. In any case ,with rising gas prices ,the benifits of lower octane fuels lower price is not worth the decrease in fuel economy and performance. This following statement holds true for virtually all vehicles on the road in ALL conditions. Use the fuel grade that provides the greatest fuel economy. This will ensure the best value for your dollar (and performance) with no possible chance of engine damage.

 

[quote]ORIGINAL: dankhound

I consider myself to be a pretty good engineer (mechanical P.E.). This isn't a totally accurate statement. Examining and performing analysis on all examples and combinations of conditions may not be feasible or economically sound, especially when those examples are not statistically significant.

In the end sometimes you have to shrug your shoulders and assume that the end user is going to follow the manufacturer's recommendations and instructions... little things like maintenance schedules, using OEM spec replacement parts and oil, using minimum RON + MON / 2 fuel...... I personally wouldn't 'what if' the scenario of running 85 octane fuel... wouldn't be worth the money spent on the analysis...