Which petrol

[sparkypete]

What fuel do you all use in your V8 motors, is normal unleaded acceptable or do you need to use an additive.

Thanks

Pete

[honourablepickle]

unleaded is ok - i tend to buy the highest octane/ron that's available at the time to cut down pinking etc. I never bother with additives etc - depends on your fueling ,ignition ,CR,and about a million other variables.
hp

[jmorgan]

Mine is nice and happy with 95. It was set up for that.

[adam quantrill]

I have to use high octane for the 'charger. However, this is variable in quality, and at the moment it's averaging 6p/l more than normal unleaded, sometimes for only 97 ron!

I have to carry an additive (Castrol Valvemaster+ at the moment) anyway, just in case I get caught out with no super. It works out at 4p/l to treat the fuel, so at the moment I run normal unleaded + additive.

If anyone knows any other reasonable octane boost treatments, please let me know.

[ed_crouch]

Strictly VPower for me.

Cos Im a man-whore.

Mind you, the spiralling costs may make me decide otherwise...

Ed.

[Richybaby]

I have to say, my car certainly doesn't seem to like the standard stuff (95Ron), runs much much better on the high octain stuff (97-99Ron), deffinitely a noticeable difference.

[D1 MAD]

Ran my 350i on 4 star then 97 ron LRP for 4 years, had to use 95 ron UL when on tour in Ireland some years ago and it ran noticeably better and kept a more even temperature so have never used anything but 95 ron UL ever since. It ticks over nice, doesn't pink and has shown 200bhp+ on two RR sessions using it.

[L33]

110 Ron

...of LPG on the 4.6 V8 BMW X5

For the V8 in the wedge, I go for Shell V Power (was called Optimax) which is 99 Ron (Was 98 Ron when is was Optimax)

To be honest, you'll get the best running out of whatever your car is set up for. If the timeing is set up for 95 RON, your unlikely to see any difference if you use 98 RON

[Brap_Brap]

I'm running on 92 octane which is the highest you can get around here, but there's 94 on the coast.
92 here is roughly 97 ocatane there. Europe uses RON (reseach octane number) where here our octane rating is more accurate, or perhaps, less deceiving.

There are two different octane ratings... RON, and MON (motor octane number) MON is the octane rating of a loaded engine at higher revs.... RON is the octane in a test tube.

Here, the number on the pump is formulaed RON+MON/2, which according to the letter I received back from Shell Canada, puts our 92 octane the equivalent of a UK 97 RON.

[ed_crouch]

Aha? my 06 Mustang V6 still drank fecking loads of it, however much chipfat there was in it!!

[FergusG]

Brap Brap,

I work at an oil refinery making this stuff. RON is not deceiving, it is just another measure of propensity to knock. MON & RON are done under different test conditions, but both are done on knock engines in a lab.

Engineer nerd.

[Brap_Brap]

FergusG said:

Brap Brap,

I work at an oil refinery making this stuff. RON is not deceiving, it is just another measure of propensity to knock. MON & RON are done under different test conditions, but both are done on knock engines in a lab.

Engineer nerd.

Fair nuff, but would not the average of the two numbers be a good indicator?

[GRIFFONMARK]

I found out from a 4 star suppliers website that my local sainsburys store has 4 star, at only a few pence a litre extra, which I have used ever since I got my 1988 350i and have no problems. My main concern was valve wear. Are these older engines OK running unleaded? Regards, Mark

[350zwelgje]

They are fine with unleaded (valve seats are ok for that, probably since RV8 used in SD1 and that is from '76 onwards). So nothing to worry about.

Rob