Wtf?

[Alexlind123]

http://www.youtube.com/watch?v=-93NBQS4qiI

Im not sure i quite understand...maybe he wont put "R" gas in his e34 because the gas is not good enough?

[Boone.Msi]

i lol'd, i would have done the same thing, my m60 gets pissed when i put cheap 93 octane in it. (ex. quicktrip, flashfoods)

Since 4 months ago, i only put chevron(with techron ) in it, i kid you not, you can tell the difference.

[Alexlind123]

I get Shell premium.

[Michael999]

i use nothing but BP premium ultimate, 98octane :)

[CharlesAFerg]

87... m20 ftw!

[DaveVoorhis]

My car's just like me -- it'll drink anything. Can't tell one octane rating, product, or advertised quality from another...

[Qsilver7]

hmmm, interesting....the BMW M30 & M20 engines were engineered to run on regular fuel (87 AKI or 91 RON) depending on which calculation your country uses. The USA uses AKI to calculate octane levels. These engines have no way to adjust for higher octane fuel.

The M50 engine was engineered to run on 91 AKI (sorry don't know what RON they're suppose to use) and the M50TU & M60 engines can run anything from 87-91 AKI because these two engines have knock sensors that will adjust engine timing to compensate for fuel octane levels. The BMW owners manual even maintains that higher octane fuels in these engines will give increased performance.

This topic is discussed ad naseum on every BMW forum I've ever been on. And for the most part...problems stem from owners not having the real understanding of what "octane" is. Many have the misconception that higher octane fuel means "better" fuel...WHICH IS WRONG. Higher octane fuel is engineered to ignite at a higher temperature...and if your car's engine can't adjust it's timing to take advantage of this effect...then you're wasting your money and possibly creating a build up of carbon from unburnt fuel.

Everyone has different claims of how different octane level fuels affect their car etc....I'm only bringing up the text that is written in the owners manual. If your experience, beliefs, or opinions are different...so be it. :p

M20 & M30 engine__________________|M50TU(w/VANOS) & M60 engine_______|M50 engines recommend 91 AKI
http://memimage.cardomain.net/member_images/1/web/433000-433999/433594_229.jpg http://memimage.cardomain.net/member_images/1/web/433000-433999/433594_369.jpg

[genphreak]

Good point, it is a very common misconception. My M30 used to drink anything but I got no improvement from premium fuels. Changed ECU chips so now she insists on 95 RON (90-91 US RON/MON). It always pre-detonates a little on any dodgey stuff, let alone 91 RON (87 RON/MON)- that is off limits now.

Time to get a knock sensor and a new ECU!

:) Nick

[indymdm]

mine doesnt like 87 octane at all i use 91 but not particular to brand