M50 on higher octane

[BMWDriver]

(Pre-VANOS M50)

Mmmmmmmmmmm! What can I say, this engine's loving it.

Well, I've been trying it since September (I fill up about once a month or so), and M50 is loving this stuff. Engine is a lot more responsive in the low end, and yesterday I had the oil changed along with having the winters put on, with this result: a super smooth runing engine! It also tends to be less jerky when I release the gas pedal in 2nd or 1st gear from a downshift, or from having to let go just to slow down when my accelerating plans are thwarted. Life is unpredictable.

And, my mileage average has gone from 12.3L per 100 km, to 10.0L per 100 km, combined highway and city driving. Needless to say I think the higher price of the fuel more than pays for itself.

Man, this car's awesome.

As a side note, here in Canada, we have three grades of octane fuel : 87, 89 and 91. Perhaps its different in other provinces though. I went from 87 to 89 and now 91 for the last two fillups at least. I understand things are different with our neighbours South of the border.

[BlackOnBlack]

Down here in the states, I only put 91...and usually Chevron...in my 525 m50. Actually, the owner's manual calls for it. 209,000 miles and runs like a charm. 22 miles per gallon combined.

[sal_park]

(Pre-VANOS M50)

As a side note, here in Canada, we have three grades of octane fuel : 87, 89 and 91. Perhaps its different in other provinces though. I went from 87 to 89 and now 91 for the last two fillups at least. I understand things are different with our neighbours South of the border.

Bloody hell. In the UK the lowest grade generally available petrol is 95 RON and the highest is 98:

http://www.petrolprices.com/about-fuel.html

[ss2115]

Australia is 92 for standard and 95 for hi performance. There is a slight difference in performance, but its not enough to warrant the extra cost.

[Russell]

My 95 specs 89 octane.

[Jon K]

All placebo - no knock sensors on a non vanos M50 so if you put trash fuel in it, it'll knock with no correction. If you add better fuel it'll just not knock - it won't add timing or anything to "better" performance. Additionally when you release your throttle pedal from a cruise you are in over-run and no fuel is being supplied to the engine at all.

[whiskychaser]

Bloody hell. In the UK the lowest grade generally available petrol is 95 RON and the highest is 98:

http://www.petrolprices.com/about-fuel.html

Spot on. Be nice if we could even compare like for like but your link suggests they pick any number of RON and put it on the pumps. Maybe why lots of you guys in the south go blown O2 sensors from that cheap stuff out of the dutch market a while ago?