How many of you run 87 octane fuel?

[Zilla]

I have to say, sheepdog has given alot of good advice in the past, its hard to go against what he says!  

I give you a +1 on da 91  sheepdogg!

[beegeezy]

If you read your manual you will find your way of driving your 318 is not good for it. The manual tells you you need to get it up above 3k regularly. In fact they give a ratio of how much above and below you should spend.

These cars were meant to be flogged, not granny shifted.

I did not know that. I think I still have the manual that came with the car, ill have to read it

[Letsplayskatch]

Too many people these days take forums too literally. Stop being such NetSperts!

[tjts1]

Dont talk trash about the intratubes.

[beegeezy]

[quinn11m20]

Cobra Jet. your are right there are many different things that can affect fuel consumption. You have to take in consideration of those factors you posted and more you probably can't think of. Later.

[nomad]

Actually, despite the higher cost of fuel, the difference between 87 and 91 is still only .20 per gallon. Really, $2 is good peace of mind to follow the manual.
Now if it was +.50 more then i'd start to think about it more.

[Poooobaa]

I run 87 all the time. No problems but I live and drive in Denver. Lower Comp. ratio you know less air at 6000 ft.

[EN318isPDX]

I only put Chevron 92 octane in my car because it says right on the gas door PREMIUM ONLY. Lower grade fuel doesnt not detonate as pure those causing "massive" wear not intended by BMW. I wouldn't use 87 octane unless you feel your cars engine is worth 2 dollars per tank. Run 92 octane or you are crazy. Better explosions are better its as simple as that.

[Choking Hazard]

Better explosions are better

Simple enough.

[bmwpower]

Cobra,
Running the tank that low all the time has a tendency to burn up the pump quicker since the fuel cools the pump.

As far as 91 octane goes, I'd stick with the factory recommended grade or higher.  The difference in price is neglible.

And I have to agree with sheepdog...just cause you don't hear the detonation doesn't mean it isn't happening.  Why dirty up that nice clean engine with cheap fuel?

[tjts1]

To each his own I guess. When you realize that the stock intake sucks in air at 158f it becomes pretty obvious why bmw requires 91 octane or better for this engine. There is nothing special about a 10:1 CR engine using 87 octane. My 10.7:1 CR volvo has been for the last 260k miles. Fix the intake problem and you can use 87 octane at all temperatures.
Also please don't tell me in not going to hear ping or knock. I've seen the difference octane can make for this engine depending on air temperature, altitude and load.

[nomad]

Lower grade fuel doesnt not detonate as pure those causing "massive" wear not intended by BMW.

Care to elaborate? You lost me on this sentence.

[EN318isPDX]

Care to elaborate? You lost me on this sentence.

Basically what I was trying to say if you run crappy gas you increase the wear on your internals..its not massive but would you not change your oil because it saves you 2 dollars?

[tjts1]

Basically what I was trying to say if you run crappy gas you increase the wear on your internals..its not massive but would you not change your oil because it saves you 2 dollars?

?
Do you have any evidence whatsoever to suggest that "crappy gas" increases engine wear?
the difference between 91 and 87 octane around here is 30 cents per gallon. I drive 12k miles per year at 30 mpg average. So that's an extra $120 of unneccesary cost per year to drive a $1000 car. Hmmmm I don't think so. How many decades do you plan to own your car exactly?
I'm completely lost in the second half of your statement.