They may come from the same place but its the additives they put in place afterwards that makes the difference. In fact they dont all come from the same refineries. Shell and BP have higher cetene levels than supermarket fuels therefore give better performance. Furthermore because of the additives they are cleaner hence some cars that use supermarket fuels get black s00t out of the exhaust the the ones that use Shell and BP are a lot greyer.
Deleted member 5241
Guest
I use only Shell (closest fuel station) and I get hardly any black clouds out of mine
not really he hasn't used any other and his car will most probably be just the same using tescos
its the same old story asda tesco etc dont produce and can up there own beans but people still buy way too expensive heinz cos they have a label they are better its all bollox
my partner was a recruitment consultant and actually saw one top name brand producing the very same stuff on the very same production lines as for asda and morrisons
ITS ALL THE SAME
its the same old story asda tesco etc dont produce and can up there own beans but people still buy way too expensive heinz cos they have a label they are better its all bollox
my partner was a recruitment consultant and actually saw one top name brand producing the very same stuff on the very same production lines as for asda and morrisons
ITS ALL THE SAME
While that is mainly true, I compeard tesco spaghetti with heinz and it is actually differnt. Its longer and thicker, so there was a distinct difference. That was only once though I hardly ever buy branded **** like that.
I'm not one for commercial market BS, which is why when my ex said shed like to live in American I told her that she wouldn't be with me...we broke up over a seprate matter however lol, but still
I'm not one for commercial market BS, which is why when my ex said shed like to live in American I told her that she wouldn't be with me...we broke up over a seprate matter however lol, but still
I dont mean to be rude but thats just rubbish. There has been countless threads on this and even factual evidence that its better.
In my own personal experience my fuel economy really suffers with supermarket fuels.
Blue Monday
Full Member
I second that, shell has a higher cetain rating hence better compresion and combustion properties. With petrol the difffereance is even more phenoninal. 5th gear tested supermarket U/L -95 RON against BP u/l 97ron and shell optimax 98.6 RON and the optimax gave something like an 18 bhp improvement in a wrx stiand a massive torque improvement(although the same tes in a small clio showed no differance). Thus higher octain better performance when used in performance engines, or in the diesel world higher cetain better performance.
course it would how can you test supermarket fuel against ultimate or optimax when they are a higher octane now if it was tested against standard bp or shell 95 RON i think you would be shocked at the very similar result!!!
Blue Monday
Full Member
If you read it properly you will see they also tested it against bp ultimate at 97RON(same RON as shell unleaded)!!! Also didn'y YOU say there is no differance between al the branded unleaded fuel so you are contradicting yourself, muppet, or as jonjay says your talkin rubbish!!!
Anyway mr sceptic this is the article
!!!!http://fifthgear.five.tv/jsp/5gmain.jsp?lnk=601&featureid=143&pageid=-1
So as my original comment said, thus a higher cetain rating should mean better performance in the right car!!!!
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there is no difference between supermarket stuff and bp as they are both 95 ron ultimate and optimax yes they are higher ron so different. lets see how is that a contradiction 95 = 95 =95 does not = 97 or 99 but i never said it did and as 1 st post did not state does your car like ultimate or optimax it just said shell fuel. ****
The supermarket petrol debate
During the 90s, in England, supermarkets started a price war with the mainstream fuel vendors by opening their own petrol stations and undercutting the Esso's and Shell's of the world by as much as 5%. People flocked to these cheap outlets without doing any proper research and after a couple of years, a lot of vehicles began to suffer as a result. There's an old saying that begins "if it's too good to be true....." In the case of supermarket petrol, there was an obvious reason why it was cheaper - it was the lower grade fuel that the mainstream outlets wouldn't take. Stuff which had been rejected in quality control, or had less additives and detergents than what you might get from Texaco or Philips66. As a result, engines started clogging up and failing emissions test. Gas mileage went down. Engines became lumpy and rough running and eventually the supermarkets were forced to fall in line with the Big Boys, so much so that nowadays they're normally less than 1% cheaper.
Skip forwards to 2005 and the summer of high fuel prices in America. Lo and behold, supermarkets started to sprout petrol stations and at the time of writing, a lot of people are in the same "cheap fuel" euphoria that the English were in 10 years ago. Sooner or later there'll be a high profile lawsuit that will put paid to that though.
As a substitute for genuinely cheaper fuel, a lot of European supermarket chains now offer cheaper fuel at a price. The catch is that you have to shop with them. Once you buy a certain amount of stuff from their store, they'll knock off a percentage of the price of petrol if you buy it from them. The fuel isn't the cheap and nasty sub-standard stuff of yesteryear that they used to use - it's good, mainstream product. But they can hide the price drop in the cost of the groceries and other items you buy in store. From your perspective, you save £2 a tank when filling up. From the store's perspective, you just spent £100 in shopping so giving you £2 back on your tank of gas is pocket change.
In America, some of the big-box chains, like CostCo and Sam's Club are now doing the same thing. Rather than go the "dodgy crappy petrol" route, they're offering discounted petrol for shopping in their stores, discounting the petrol by a couple of cents per gallon as long as you've bought more than $50 of products from them.
During the 90s, in England, supermarkets started a price war with the mainstream fuel vendors by opening their own petrol stations and undercutting the Esso's and Shell's of the world by as much as 5%. People flocked to these cheap outlets without doing any proper research and after a couple of years, a lot of vehicles began to suffer as a result. There's an old saying that begins "if it's too good to be true....." In the case of supermarket petrol, there was an obvious reason why it was cheaper - it was the lower grade fuel that the mainstream outlets wouldn't take. Stuff which had been rejected in quality control, or had less additives and detergents than what you might get from Texaco or Philips66. As a result, engines started clogging up and failing emissions test. Gas mileage went down. Engines became lumpy and rough running and eventually the supermarkets were forced to fall in line with the Big Boys, so much so that nowadays they're normally less than 1% cheaper.
Skip forwards to 2005 and the summer of high fuel prices in America. Lo and behold, supermarkets started to sprout petrol stations and at the time of writing, a lot of people are in the same "cheap fuel" euphoria that the English were in 10 years ago. Sooner or later there'll be a high profile lawsuit that will put paid to that though.
As a substitute for genuinely cheaper fuel, a lot of European supermarket chains now offer cheaper fuel at a price. The catch is that you have to shop with them. Once you buy a certain amount of stuff from their store, they'll knock off a percentage of the price of petrol if you buy it from them. The fuel isn't the cheap and nasty sub-standard stuff of yesteryear that they used to use - it's good, mainstream product. But they can hide the price drop in the cost of the groceries and other items you buy in store. From your perspective, you save £2 a tank when filling up. From the store's perspective, you just spent £100 in shopping so giving you £2 back on your tank of gas is pocket change.
In America, some of the big-box chains, like CostCo and Sam's Club are now doing the same thing. Rather than go the "dodgy crappy petrol" route, they're offering discounted petrol for shopping in their stores, discounting the petrol by a couple of cents per gallon as long as you've bought more than $50 of products from them.
Octane and power
It's a common misconception amongst car enthusiasts that higher octane = more power. This is simply not true. The myth arose because of sportier vehicles requiring higher octane fuels. Without understanding why, a certain section of the car subculture decided that this was because higher octane petrol meant higher power.
The reality of the situation is a little different. Power is limited by the maximum amount of fuel-air mixture that can be jammed into the combustion chamber. Because high performance engines operate with high compression ratios they are more likely to suffer from detonation and so to compensate, they need a higher octane fuel to control the burn. So yes, sports cars do need high octane fuel, but it's not because the octane rating is somehow giving more power. It's because it's required because the engine develops more power because of its design.
Octane and gas mileage
Here's a good question : can octane affect gas mileage. The short answer is absolutely, yes it can, but not for the reasons you might think. The octane value of a fuel itself has nothing to do with how much potential energy the fuel has, or how cleanly or efficiently it burns. All it does is control the burn. However, if you're running with a petrol that isn't the octane rating recommended for your car, you could lose gas mileage. Why? Lets say your manufacturers handbook recommends that you run 87 octane fuel in your car but you fill it with 85 instead, trying to save some money on filling up. Your car will still work just fine because the engine management system will be detecting knock and retarding the ignition timing to compensate. And that's the key. By changing the ignition timing, you could be losing efficiency in the engine, which could translate into worse gas mileage.
all from the car bible website
i have tried this octane theory on my punto jtd by putting avtur (aviation jet fuel in the tank) it is basically very refined diesel and equivelant to 108 ron. my punt managed a measly 3 mph more top speed and same fuel consumption
It's a common misconception amongst car enthusiasts that higher octane = more power. This is simply not true. The myth arose because of sportier vehicles requiring higher octane fuels. Without understanding why, a certain section of the car subculture decided that this was because higher octane petrol meant higher power.
The reality of the situation is a little different. Power is limited by the maximum amount of fuel-air mixture that can be jammed into the combustion chamber. Because high performance engines operate with high compression ratios they are more likely to suffer from detonation and so to compensate, they need a higher octane fuel to control the burn. So yes, sports cars do need high octane fuel, but it's not because the octane rating is somehow giving more power. It's because it's required because the engine develops more power because of its design.
Octane and gas mileage
Here's a good question : can octane affect gas mileage. The short answer is absolutely, yes it can, but not for the reasons you might think. The octane value of a fuel itself has nothing to do with how much potential energy the fuel has, or how cleanly or efficiently it burns. All it does is control the burn. However, if you're running with a petrol that isn't the octane rating recommended for your car, you could lose gas mileage. Why? Lets say your manufacturers handbook recommends that you run 87 octane fuel in your car but you fill it with 85 instead, trying to save some money on filling up. Your car will still work just fine because the engine management system will be detecting knock and retarding the ignition timing to compensate. And that's the key. By changing the ignition timing, you could be losing efficiency in the engine, which could translate into worse gas mileage.
all from the car bible website
i have tried this octane theory on my punto jtd by putting avtur (aviation jet fuel in the tank) it is basically very refined diesel and equivelant to 108 ron. my punt managed a measly 3 mph more top speed and same fuel consumption
Yes, thanks Muddy, keep it civil or don't bother. Also rather than chucking what is copyrighted material from another website all over the forum, can you just link to it.
Thank you.
Thank you.
Deleted member 5241
Guest
, go on, which type of jet did you get that from then??
In theory, you could buy avtur from the majority of airfields around the country, because it isn't just jet aircraft that need avtur - many helicopters have turbine engines that run on it too. But whether you could persuade the fuel guy to serve you is another matter.
But I really don't recommend running a diesel engine on avtur. It'll work in the short term, mainly because diesel engines will burn almost any oily fuel, but avtur doesn't have the lubricating qualities necessary to protect the injection system of a car diesel engine.
Diesel engines have, in the last few years, become available as replacements for avgas-burning piston engines in light aircraft. Those engines are derived from car engines, but I'm not sure of the details how they overcame the problems caused by the difference between avtur and normal diesel fuel.
But I really don't recommend running a diesel engine on avtur. It'll work in the short term, mainly because diesel engines will burn almost any oily fuel, but avtur doesn't have the lubricating qualities necessary to protect the injection system of a car diesel engine.
Diesel engines have, in the last few years, become available as replacements for avgas-burning piston engines in light aircraft. Those engines are derived from car engines, but I'm not sure of the details how they overcame the problems caused by the difference between avtur and normal diesel fuel.
Deleted member 5241
Guest
In theory, you could buy avtur from the majority of airfields around the country, because it isn't just jet aircraft that need avtur - many helicopters have turbine engines that run on it too. But whether you could persuade the fuel guy to serve you is another matter.
Underlined bits = Same thing
One is just a bit bigger than the other in most cases.If you work on them you wouldn't have to buy it, you could "borrow some" during a shutdown (some fuel leaks away from drains during shutdown) or turnround (wingbox drain points) for instance. Keeping to topic, Shell supply AVTUR and AVGAS.
I immediately thought Jet as thats all I've ever worked on, only ever worked on a Helicopter simulator which isn't quite the same. Much quieter and no spinning sharp bits on top or at the back.
you can borrow some if you work in a fuel tank department on an airfield that has to drain and test said tanks. it does burn too hot in the long term and does warp heads and knacker pumps but by adding 70-30 mix with diesel or a mineral oil or veg oil it does then have some lubrication.
Must say that I've only ever put Tesco cheap stuff in my FR - now has approx 13700 miles on the clock over a period of 8 months and it's loosened up helll of a lot - also i've learnt how to drive it efficiently which I think is what's probably made the biggest difference to my mpg readings.
I'm now consistently seeing 550-600 per tank - it is a little sooty but i've found that that tends to happen when you boot it after driving carefully a lot...
I'm now consistently seeing 550-600 per tank - it is a little sooty but i've found that that tends to happen when you boot it after driving carefully a lot...
Blue Monday
Full Member
Octane and power
It's a common misconception amongst car enthusiasts that higher octane = more power. This is simply not true. The myth arose because of sportier vehicles requiring higher octane fuels. Without understanding why, a certain section of the car subculture decided that this was because higher octane petrol meant higher power.
The reality of the situation is a little different. Power is limited by the maximum amount of fuel-air mixture that can be jammed into the combustion chamber. Because high performance engines operate with high compression ratios they are more likely to suffer from detonation and so to compensate, they need a higher octane fuel to control the burn. So yes, sports cars do need high octane fuel, but it's not because the octane rating is somehow giving more power. It's because it's required because the engine develops more power because of its design.
Octane and gas mileage
Here's a good question : can octane affect gas mileage. The short answer is absolutely, yes it can, but not for the reasons you might think. The octane value of a fuel itself has nothing to do with how much potential energy the fuel has, or how cleanly or efficiently it burns. All it does is control the burn. However, if you're running with a petrol that isn't the octane rating recommended for your car, you could lose gas mileage. Why? Lets say your manufacturers handbook recommends that you run 87 octane fuel in your car but you fill it with 85 instead, trying to save some money on filling up. Your car will still work just fine because the engine management system will be detecting knock and retarding the ignition timing to compensate. And that's the key. By changing the ignition timing, you could be losing efficiency in the engine, which could translate into worse gas mileage.
all from the car bible website
i have tried this octane theory on my punto jtd by putting avtur (aviation jet fuel in the tank) it is basically very refined diesel and equivelant to 108 ron. my punt managed a measly 3 mph more top speed and same fuel consumption
Okay so you copied 3 informative paragraphs to say what in effect i said in 1 line.
The link to the 5th gear site also said the same thing, thats why the WRX STI produce significant more power and torque on optimax instead of supermarket fuel or 95 ron fuel but in the renault it had no effect as one car could make use of the higher octain fuel the other couldn'e ie it works in the right car. Modern VAG cars have adaptive ECU's so can benifit from the use of better cetain or octain ratings.
The reason i use shell diesel extra is it has a higher cetain rating so the car, especially with its revo remap can make better use of it.
You ask any Remapping company and they recomend higher cetain diesel like shell extra (the one questioned in the title) or BP ultimate
or vmax (formally optimax) for petrol cars!!!!!
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