Petrol Octane - Was: Considering a BMW - A Few Questions

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Was just reading the "Considering a BMW - A Few Questions" and I was curious after seeing a few of the replies.
Over here in the UK you've got a choice of 2 types of unleaded "gas".
IIRC you've got bog standard unleaded at 95 octane, and super (aka expensive) unleaded at 98.
The old 4 star leaded was about 99-100.
Yet I see you guys in the USA talking about 92 Octane and below, which has come as a shock because as far as I can remember that was what we used to call 2 star and would only run lawn mowers on!
Is that quality of fuel that common?
I remember hearing some story as to why the E36 TD and TDS models from the 90's didn't go to the states, and that was the diesel quality was so bad they wouldn't run properly... At the time I just thought, Nah, gas is so cheap over there they don't feel the need for a diesel car, but now I'm starting to wonder!
Dodgy.
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Octane is measured differently here in the states. Google search for Octane MON RON PON
Cheers
Dodgy wrote:

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Different measurement standards:
UK 98 RON = U.S. 93 Pump octane (Premium) UK 95 RON = U.S. 89~90 Pump octane (Mid-grade) U.S. "Regular" is 87 Pump octane
BMW specifies 91 octane in the U.S., approximately equivalent to 96 octane in your neck of the woods.
Complicating matters is altitude. In higher altitude areas in the western U.S., regular gas can be 85 octane with mid-grade at 88 and premium at 90~91.

Right now, diesel is 20~25% more expensive than mid-grade gas in the U.S.
Hope this clears things up for you.
Tom K.
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Yes, and the old UK 4-star leaded was 98 octane, IIRC, not 99-100.
Actually, Shell does 98 but some (e..g Total, BP?) offer 97...
DAS
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Back in the 1970's, most major U.S. brands had 95 PON (ca. 100 RON) and Sunoco had 96. When leaded gas was beginning to be phased out and octane fell around 1978, the Maryland State Comptroller decreed that the new 93 octane gas could not be advertised as "Premium" in the state. IIRC, that lasted only a couple of years and now even 91 (your 95 or 96) is described as premium.
Tom K.
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That is precisely why only the octane number matters. "Premium", "Super" etc have absolutely no widespread meaning. Even in Europe there are different words for the same thing, partly connected with what exists below the standard 95 octane.
DAS
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Yup. It seems strange to me it's called this in the UK given it's the lowest octane petrol available - and always has been for unleaded. Regular would be a better name.
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On Tue, 20 Dec 2005 23:20:54 -0000, "Dori A Schmetterling"

I was actually unsure, it being a while since I saw it, so I googled... I came back with a variety of values for 4 star, one specifying 99.7... So I punted for that value. :-)
Dodgy.
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Tom K. wrote:

Not for all models. For both of my older ones the Owners Manual specifies 89 or better.
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By the present tense "specifies", I meant to include only current models. In my area, if I want 91, I have to mix 93 and 89, so 89 would be easier - but would probably mean slightly lower compression.
Tom
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Some are 97.

100 octane was 5 star. 4 star was more commonly 98. 5 star disappeared around '70.
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Talking "diesel" and the USA on other news groups I came to the conclusion that as an oil grade much the same as diesel is commonly used for household heating in the USA, where in Eurpope a lot of heating is done with Natural Gas, diesel is much more expensive in the USA as the supply of that grade of oil is being used for heating. Therefore no point in running cars on diesel over there. Someone correct me if I'm wrong...
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In the UK diesel costs more than petrol. Diesel cars are still cheaper to run.
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waffled on about something:

We have oil heating too... Often found out in the sticks where the gas companies couldn't be bothered to run a pipe.
It's much much cheaper than car diesel, most probably due to the tax man not putting a huge mark up on it, but I don't know how suitable it is for running vehicles... Not sure I want to risk my engine to try it!
I'd be interested to know how expensive it is over there, it's probably cheaper than ours, but compare to your petrol prices it probably looks expensive.
This week I filled up at 90.9p a litre...
So 3.785 litres to the US Gallon = 344.1p a US Gallon
Yahoo exchange rate $1.75 to the
$6.03 for a US gallon.
Jeeez, I think I'm gonna try out the fuel oil!
Dodgy.
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There are basically two types - one really paraffin, the other diesel. The diesel may not have the same additives as road fuel, though, but a car would run on it ok. If caught, the fine is very large.
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On Wed, 21 Dec 2005 11:16:10 +0000 (GMT), "Dave Plowman (News)"

I remember when we had the last fuel protests, the revenue men decided it would be a good time to catch people being naughty and started dip testing all the obvious diesels (land rovers, vans etc) to see if they were running on red farm diesel.
They'd have fun with my landy though... 2 tanks... 2 different fuel circuits... and a completely legitimate use for the red... Off roading :-)
Dodgy.
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Dodgy wrote:

Different calculations of Octane.
http://www.btinternet.com/~madmole/Reference/RONMONPON.html
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On Wed, 21 Dec 2005 11:08:40 -0500, Malt_Hound

Oh typical eh!
Not content with having 4 fluid ounces missing from their gallon (bit of a shock when you order a beer in the USA), the quality of fuel is even measure differently! Oh and 110volts missing from their electrics and an extra 10hz on it instead... hehe...
Oh and having to drive on sidewalks instead of pavements... Blimee it's all just to much for me old noggin'!
Dodgy.
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not*yahoo.com"> waffled on about something:

See, if it weren't for all that and Lucas electrics, we might have remained British subjects! You guys could now have all the responsibility for Iraq as well as a $3 trillion debt!
Tom K.
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On Wed, 21 Dec 2005 13:35:24 -0500, "Tom K."

Oh no, you can keep the prince of darkness... Then again, having owned an Italian car, I think Magnetti Marelli might be in the running too!
As for the debt, we're doing quite well on or own thanks. What we haven't spent in Iraq, our beloved leader has decided to give to the needy people of France *cough* sorry, Europe.
Dodgy.
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