petrol.

ill just point out that alot of fuel companys supply the same fuel to different stations (ie)asda/bp use the same fuel

agreed.

they all get it from the major suppliers, its not like tesco have there own oil rigs and petrol processing facilities.

I used to be involved with the transport engineering side of the petro/chemical industry and our tankers used to load at the same location as many of the majors like ASDA, Tesco and Morrisons (I have done the pick-ups work myself) and you can be assured its all the same juice.

However Shell is different they do have their own facility.

I have used a spreadsheet for fuel consumption and cost for many years and this indicates using Shell standard grade is more cost effective than the rest, but using V Power is not so good as the advertising would suggest. That of course is only me and my boring spreadsheet opinion.

The standard joke amongst tanker drivers was if Shell 1203 got spilt it would go in their own car tank not so with the rest of the stuff. Believe me messing about with large amounts of hazardous liquids (typically 29,000 liters a load) is not taken lightly and things did not get spilt.

Grasshopper wrote: I used to be involved with the transport engineering side of the petro/chemical industry and our tankers used to load at the same location as many of the majors like ASDA, Tesco and Morrisons (I have done the pick-ups work myself) and you can be assured its all the same juice.

However Shell is different they do have their own facility.

I have used a spreadsheet for fuel consumption and cost for many years and this indicates using Shell standard grade is more cost effective than the rest, but using V Power is not so good as the advertising would suggest. That of course is only me and my boring spreadsheet opinion.

The standard joke amongst tanker drivers was if Shell 1203 got spilt it would go in their own car tank not so with the rest of the stuff. Believe me messing about with large amounts of hazardous liquids (typically 29,000 liters a load) is not taken lightly and things did not get spilt.

I'm not disputing your observations but if it all comes from the same place is randomly interchangable with the exception of shell how come does our jimny not like asda and then run lovely on bp, how does that work?

At work we have large problems with diesel in the winter, in freezing conditions it waxes up clogging filter bringing eml lights on, it has been concluded that 'supermarket fuels' are to blame, other sources have said its 'summer fuel' that is still being used in winter months causing the problems, I wouldn't know the process of refinery, what goes into the fuel, who supplies who, but I know it's a big enough problem that the company pay for fuel filters to be changed when the fault occurs.

As for petrols I can't say we've suffered the same problem. I personally have run all my vehicles on 95/ 97/99 Ron and can say I've never noticed a difference, but all my engines have been in a fairly standard form. I have a friend with a cupra r that's had the tits tuned off it, if he runs it on regular fuel it brings the eml light on!

My cousin had a cbr600 that was imported from America, it used to idle high as the 'pump gas' that the bike was mapped for in America is a much lower octane than European fuel.

In comparison it's recommended that jap imports (mostly performance motors) are run on high octane as the regular fuel in Japan is a higher octane, the cars are mapped for the fuel available.

The octane of fuel does make a difference, but with all the other factors involved it's not likely that you will notice a difference, if you do it probably won't be massive.As for the matter of is it worth spending the extra money on fuel for the return, someone in a lab would probably say yes with experiments to prove so, personally, my jimny gets whatever fuel is in the pump of the forecourt that I happen to turn up too :laugh:

High octane petrol doesn't contain any more energy than low octane petrol, therefore an engine that runs fine on 95 octane will not produce any more power on high octane fuel. The higher octane rating simply means the fuel can be compressed more before it detonates. If you have a turbocharged engine, higher octane fuel will allow you run higher boost pressure without detonation (knocking). In naturally aspirated engines it will allow you to run a higher compression ratio.
As the Jimny engine is neither turbocharged nor a high-compression engine it will run at it's optimum on standard unleaded petrol. Any differences observed when using premium fuels will be either due to the additives, or a placebo effect.