Different countries measure octane differently...they measure different aspects of 'ignitability'...under different conditions, etc.

They 'cut' pure petrol with different additives...detergents to clean fuel injectors, etc. That's what creates 'brand differences'. I'm sure a lot of it is "snake oil", but I swear the 360 used to run better on Shell's 95 than anyone elses (including the other 'premium' brands)....no idea why....

cheers

James

Thanks and.... wierd dont you think?

I think i'm going go back to using standard 95 i can't really justify the extra cost and i haven't really seen much difference in mpg as i have mentioned elsewhere it'll still only do 25mpg so it hasn't helped that. Thanks for the advice

^^ What he said, there are two different measurements of octane rating, depending on what conditions you use. There's Research Octane Number (RON) and there's Motor Octane Number (MON)

In the UK, you always hear about RON, which is 99 for V-power and Tesco, 97 for all other Super Unleadeds, and 95 for normal Unleaded.

MON is always a lower number and is relevant, but is never quoted. The Americans, bless them, take the mean average between RON and MON as their number which they publish on their pumps.

BTW, Tesco uses Bio-Ethanol in their 99 octane to get that rating. Its good stuff, but I found that it used slightly more fuel than v-power. I had to reset all my fuelling to lean the mixture off slightly when I switched from Tesco to V-power.

Have now adjusted it back to how it was, started first time this morning and seemed alot happier on choke. This car is just so slow!!!!!!!! it idles well, starts well but put your foot down and nothing it feels so strangled!

germ wrote: set standard but octane is differnt if v-power is 98 and the supermarket stuff is 98 then its the same!

In theory that should be the case, but 'real world' experience tends to say otherwise.

Take the recent trip to Belgium that Foggy, Pettaw, Farrell360, ChrisC and myself made with Foggy's 245. We started off on supermarket 95 fuel and the car was ok despite it really needing 97 fuel. Once we collected the empty trailer the car wasn't too happy and was even worse once the trailer was loaded. A fill-up with BP Ultimate 97 seemed to improve things back to 'pre- loaded trailer' conditions but a further fill-up with Shell V-Power 98 had the car running better than it had been without the trailer.

Both BP Ultimate 97 and Shell V-Power 98 are of the correct octane rating for the car, but the car was noticeably better on Shell than BP.

fume wrote:Have now adjusted it back to how it was, started first time this morning and seemed alot happier on choke. This car is just so slow!!!!!!!! it idles well, starts well but put your foot down and nothing it feels so strangled!

It should be quite lively. It would pay to get the fuel mixture checked properly if possible. There are various possiblitys as to what the problem is but the fuel consuption shows things are not right.

And saying about octane number...Here is believed ( well fuel industries does ) that mixing benzine with the water, oil ( motor, brake....whatever ) will make car run faster, and better .

Several years ago ( i think 1998-9 ) when we filled the tank to the full on some gas station, car would go like somebody kick them from behind contentiously. When we got to the parking we took some gas from the tank out and.....surprise !!!!
There were more f**** water inside than there were gas. Imagine that.....paying for water .

Now its off the road due to the propshaft problem i intend to have a good look at everything, carb off and rebuild if necessary, there is definitely something not quite right. I have had the mixture checked and the guy said it was ok, but that doesn't mean a thing!