The old 'Which fuel?' chestnut

[Sp!ke]

Found this on another forum which makes for interesting reading.

Super unleaded is a fine fuel, but only if purchased from reputable dealers. Esso SUPER, like BP are about the best you can buy. Supermarket stuff is just 4 star without the valve addictive, which itself is just 95 unleaded that has been octane boosted. AVOID AT ALL COSTS. Supermarket petrol is a very dirty fuel. Any engineer of their pumps will confirm that. I have seen the results of their filters and you get everything from feathers to god knows what flowing through supermarket fuels. EVEN SAND.

All Super by law has to be 97 ron, but where its stable enough to hold higher octane, stations are able to advertise its octane as being higher sometimes.

Optimax has a variable octane rating, due to its structure its less stable, but leaves the refinery at 101 octiane. Thats the equivalent to the old 5 star for those old enough to remember it. By the time you buy it, its closer to around 97. This is why its octane isnt always stated.

Normal 95 or 97 fuels wont lose octane, whereas optimax does, but used fresh, its the highest octane fuel you can buy.

All supermarket fuels come from either the Matex or Purfleit refineries for the south east. These only take oil from the eastern block. They are most definately NOT the same fuels as ESSO and such like. They also remix contaminations for other companies then sell the fuel on via supermarkets as well. On average, each 50 litres brought from a supermarket will have 8% contaminates, and 9 grams of grit. I have got 2 test tubes sitting on my desk at work of both ESSO and Tesco regular 95 for simple comparisons when arguing these points with supermarket buyers. There is a bead in both which on the Tesco tube floats in mid suspension due to the grittiness of its petrol. The ESSO falls straight to the bottom. These are random samples taken every few weeks, and the results are always the same.

Texaco is a subsidary of ESSO and both use the same petrol.

There are basically 3 companies which supply fuel to the UK. ESSO, BP, AND SHELL.

Each sells to all the other names you find.

JET, FINA, Q8 and a few other smaller outlets all use SHELL.

TEXACO and TOTAL use ESSO,

Supermarkets use Eastern Block fuels, which are primarily designed for the 91 Ron continent market. These are upgraded in the UK to UK specs by using Butane gas. Hence to avoid.

BP Ultimate is just its old Super grade cleaned up a bit. IE. It goes through another filter at the refinery. Not a bad fuel though, second only to ESSO in quality. Its Diesel is the best in the world for all you Diesel owners.

OPTICRAP. Need i say more. All grades supplied by Shell. Might as well fill from your local FINA station and pop a bottle of Halfarts octane super duper booster plus in.

ESSO 95 and 97 = If you want every pennies worth in quality petrol, look no further. Get it at your local TOTAL, TEXACO or ESSO now

 

[Vlad]

Interesting read and confirm my suspicions of supermarket fuel which have made my various motorbikes run like absolute dogs

 

[Shude]

I've only ever run my cars on Asda/Tesco fuel, I've not really noticed any problems.

 

[BenzComander]

Would have to agree. My Smartie hated supermarket fuel but went like stink on Optimax There was a hugh debate on this one on the Smart forum Funkysmart.

 

[Flyer]

Very interesting. I only ever use Shell Optimax. Works for me.

Something tells me that chap works for Esso ...

 

[Steve_Perry]

I happen to shop at one particular forecourt in my local area only because they are the cheapest. They also just happen to be an Esso station but they usually undercut even the local supermarkets too. Until recently I also used to shop at a couple of other local Esso petrol stations too only because they were usually the cheapest for fuel but they were closed down/demolished late last year so now I just stick to the one.

The strangest incident was in Oct last year... I was in a Esso station in NW London and the 97Ron super (whatever they call it) was only 1p/litre more expensive than the 95Ron standard unleaded Filled up with super on that occasion haven't done it since tho'.

S.

 

[Satch]

Can certainly endorse the bit about BP Ultimate diesel. Good stuff and as well as making things better all round actually smells less than some diesel.

In short, diesel fuel quality is variable. Some vehicles are designed to be less sensitive to poor fuels but a modern "performance" diesel needs to be fed a quality diet. Wrote this a while ago: my personal view (right or wrong, make your own mind up) of additives & use of Veggie oil as a fuel but may help to explain fuel quality in the diesel context.

"No doubt that there were problems with low sulphur fuels when used in early generation high pressure systems. They rely on the fuel for lubrication and sulphur compounds were key to that. But most fuel majors sorted that by putting some lubricity additives in to base stock fuel and Bosch did some fixes.

But some cheap diesel is just that, sometimes very nasty in terms of fractions, few additives and general crud in it so I would always put additives in.

Mid range branded stuff from a major will be standard diesel and has a basic additive package. Sometimes flogged as "City Diesel" or a "Premium" fuel by using better quality base fuel and bunging more of this sort of stuff in at the refinery:

http://www.infineum.com/products/fu...nce/diesel.html

BP Ultimate etc is a concocted with much better quality fractions and additive package.

Sticking good quality veggie oil in helps as this is an excellent fuel but something many are still not sure about. Yes, it works no problem when in modest concentrations (20%), provides lubrication and some extra kick because of the oxygen content in the oil but I for one am not sure about the gums & resins. Maybe it is a non issue in a diesel mix with additives but I do not know that yet. If somebody produced a source of degummed quality vegetable oil I would have no hesitation in using it in a mix.

"Bio diesel" is not the green wonder many would have you believe. In chemical terms pure bio diesel is pretty vile. It is a Methyl Ester, has lubricity issues coupled with the ability to degrade some seals and is variable in heat output because that depends on the quality of the base vegetable oil or fat it is made from. That is why "Bio Diesel" sold in the UK tends to be 95% conventional diesel and 5% Methyl Ester with an additive package. Or if you are a cynic bog standard diesel with a bit of vegetable derived Methyl Ester so you can put a "green" marketing spin on it.

Cetane number is often considered to be the diesel equivalent of Octane rating but really it is a measure of a fuel's ignition delay, i.e the time period between the start of injection and start of combustion of the fuel. Higher cetane fuels will have shorter ignition delay periods than lower cetane fuels, are easier to burn when cold and run smoother. All good stuff so far.

But Cetane number alone is not a measure of fuel quality! Stick enough Cetane improver in a really crap base fuel with a low heat value and you can have a high Cetane rating fuel because it ignites quickly but providies poor energy output and the car will underperform.

Put way too much Cetane improver in and you may cause too short an ignition delay which changes the peak pressure timing & can in some engines give a loss of power!

Car makers put the "no additives" bit in to stop warranty claims or being sued if it all goes horribly wrong. They cannot and will not say "use X, not Y" fuel additive and do not want in general terms to upset the oil indutry by suggesting that their product needs to be augmented.

So, I use BP Ultimate or some "Premium" diesel and Millers Diesel Power plus. It does ramp up the performance but lubrication and injector cleaning is also a consideration here. Net results are good because Millers is in essence a Cetane improver with lubrication & cleaning additives but I do not overdo it and am happy enough to run on decent diesel alone for a while.

Diesel engines are designed to cope with a range of fuel quality but you cannot escape the fact that better quality fuel will give better results. Additives in modest doses just help that process along a bit and if these assist with lubrication and keep the injectors clean so much the better"

 

[Benzowner]

I've only ever run my cars on Asda/Tesco fuel, I've not really noticed any problems.

Maybe you would notice it running better on BP or Esso or Shell

 

[DITTRICH]

...texaco 97 ron would seem to be a good choice to compare to the asda stuff i normally use. I have sufficient fuel usage history (3m) to be able to see if it makes a difference.
Regards
Les

 

[scotth_uk]

I have tried all of the fuels available, and have generally tried to do 2 or 3 tanks in a row of the same fuel to get the feel. Can't say I notice anything different at all with any of them.

I normally use Sainsbury's 97.

 

[GordonTarling]

All that is only one person's opinion and, frankly, I feel that it's a lot of hogwash. I read a post some time ago on another forum from an ex fuel delivery driver who swore that the only difference between the fuels was the additives which were added as they filled his tanker!

 

[Robbo]

And I know of someone who works at Exxon (Esso) who said that they supply some supermarket fuels.

 

[Satch]

All that is only one person's opinion and, frankly, I feel that it's a lot of hogwash. I read a post some time ago on another forum from an ex fuel delivery driver who swore that the only difference between the fuels was the additives which were added as they filled his tanker!

Indeed and that is a key point. Petrol sold in UK (except Shell Optimax which is blended up differently) is in theory the same base product into which each company puts in their own additive package.

There are inevitably some variations in the base stock though because of the way different refineries blend it up and how old it is because the dissolved gases & higher fractions tend to leach out over time. (That is a favourite as to why the lawnmower is difficult to start in the spring: the petrol has degraded and needs to be changed for fresh. Worth noting Optimax degrades quite quickly so only buy it from a busy site.)

So you will tend to see all kinds of tankers filling up at a distribution site and they fill up with the same base fuel. They share distribution points in order to reduced transport costs, but a company will add their own chosen additive package at the filling gantry.

Some additive packages are better than others and the better ones are not cheap. The quality and dose rate of additives in petrol makes a lot of difference in engine performance, wear, cleanliness and emissions.

In diesel terms BP Ultimate is blended up from better quality fractions and has an advanced additive package. Basic diesel stock tends to be far more variable in quality than petrol because, put bluntly, producers could sell almost anything than the very grim stuff without the majority of diesel users noticing a thing. Lower expectations perhaps but the new generation of high performance diesels is changing that rapidly.

Most petrol users however can soon tell if they haved pick up a load of duff fuel.

 

[pammy]

I agree - get duff fuel and you know - but by and large it's all the same to me. I've given Edna a couple of tanks of Sainsbury's super unleaded and can't say I've noticed a real diff. The increased MPG is since the service and after a run - not on better fuel.

 

[drifting]

Just had to ask, but who supplies Elf then? I have been filling my C270CDI up there most of the time, did also try City Diesel and only noticed a degradation in performance ..

Regards Paul.

E320CDI coming next week, whoopieeee

 

[fuzzer]

I use shell / esso or jet cause thats where my fuel card works.

I buy 95 ron and Never had any problems. Car goes the same with all of them.