525i and 325i top octane...

[0bmw]

I have a 03 325i and a 04 525i and recently I noticed that on the fuel cap it says minimum octane 91 not recommended octane. This makes me think I could use higher octanes to get better performance, how high can I exactly go?! 100?!!!, maybe mix 100 with 91?!!! has anyone done this?

[Torque]

I use 91 or 93... whichever happens. 100 is like race gas... it would cost you way too much, and the chances are you won't notice any performance gains.

If you turboed or supercharged your car and had other mods, then it would be worth it... this way just stick to 91 or 93.

[BeelZibub]

Over here 95 octane is the basic cheapo petrol & 98 the premium. And there is a great deal of difference - smoother running, better starting, sharper throttle response and better fuel economy from the latter.

All the boyracers usually add an Octane additive to their petrol too giving even more performance - some even have an additive with Nitrous oxide in it.

I can only imagine that running a modern car on 91 ron must make it run like a bag of shit.

[CosmosBlack]

I have always used 93 minimum.
I figured there's no point in saving a few cents a gallon.
If you can afford a bimmer, you can afford premium gas...right?
Don't know about you...but I love my car! :lol:

Oh, beelzibub, over here,
Regular - 87
Super - 89
Premium - 93

[CosmosBlack]

I think on my gas cap... it says minimum 89 octane.
I've been tempted to try that just to see the difference
but something always tell me...Naaaaahh :P

[BeelZibub]

Sorry Just done my research (should have done it first I guess)

Here in UK we rate in RON in other countries they rate in MON (which gives a higher number than RON) and in the US you use PON, which is an average between MON & RON.

So your 91 octane (PON) = our 95 octane (RON)
Your 93 octane (PON) = our 97 octane (RON)
So our premium 98 (recommended for bmw's and all other performance cars)would equal your 94.

The 100 you were talking about therefore becomes akin to bloody rocket fuel

Actually if you read into it a little, the petrol companies are bloody clever at legally selling crap batches of petrol.

[CosmosBlack]

Did Confucius invented these gasoline ratings?

[BeelZibub]

Originally posted by CosmosBlack@Aug 24 2004, 11:26 AM
I think on my gas cap... it says minimum 89 octane.
I've been tempted to try that just to see the difference
but something always tell me...Naaaaahh :P

You would definetly see a difference - A lot of people over here say I can't see the difference in them so I just use the normal stuff - this usually means they are too tight to dig a little deeper in their pockets and pay the extra.

Saying that though, I filled up yesterday with premium at 89 pence a litre which equals 1.60788 USD. Mind, you don't use litres do you so I'll try and convert it better for you 3.79 liters per US gallon = $6 and 9 cents per gallon - would you guys pay this to run your car??? Of course we in the Uk just love being ripped off by the rich fucking oil companies and our crappy fucking bush loving government.

[CosmosBlack]

1 US gallon = 4 liters (not 4.5 liters)

Where I am in Florida (different locations, different prices) today,
it was $1.97 a gallon for premium.

[BeelZibub]

US Gallon = 3.79 litres not 4 (and I never said it was 4.5)

[BeelZibub]

or 3.785 to be more precise

[BeelZibub]

That means we pay 3.09 times as much for our petrol as you.

[CosmosBlack]

No, I didn't say you said it was 4.5
What I was trying to explain was
In England, 1 gal=4.5 liters
In US, 1 gal=4 liters

[BeelZibub]

Why can't the world just get it's shit together then I wouldn't have all these arguments in threads about bhp/sea bhp, us/imperial gallons, ron/mon/pon, $/£, I blame it on the bastard French.

[CosmosBlack]

:lol: Yeah right! Let's just blame it on the truffle-sniffing pigs then!