Alex V wrote:northernhenry wrote:The difference being what?
Do you actually notice day to day?
I dont notice day to day as my tank takes 2 weeks to empty between fills, but with a small car i had once filling with shell/bp it got more mpg and ran smoother, now i have a bigger car the same applies. I coudnt go back now.
btw I find shell in particular very competitive and usually within a penny whereas bp always seems substantially more.
cheers
alex
I knew I shouldn't have got involved in this one but as this industry is my passion, here goes....
All oil based products come from miles below the Earth's crust and has to be refined into various usable products. 2 of these products are Petroleum Spirit (Petrol) and Heavy Fuel Oil (Diesel or Derv).
The actual refining process is the same throughout the World, regardless of which Oil Company or refinery processes it. The refining process then gives you a base product.
The base product can then be sold "as is" without any further refining or additives. This is the sort of product that supermarkets buy and re-sell without any additives and therefore no extra cost.
Now the major oil companies have realised, correctly in my view, that modern car engines need a more "complex" fuel in order to ensure emissions legislation is met and that engines are run without damage to the internal components. A good grade of engine lube oil is the main factor in keeping an engine in tip top condition but a good "burn" of the fuel also helps by preventing build up of carbon deposits and incorporating detergents in the fuel additive.
Some additives also boost the engines performance and whilst a more expensive product gives an overall better burn (Shell V Power, BP Ultimate and Esso Energy Supreme are examples of these higher grade fuels) their normal product range is superior to the supermarket juice.
In short, fuel without additives will probably damage engines quicker, albeit not too noticeable until a higher mileage has been reached. The fuel grades from the major oil companies gives your engine better protection against wear, helps keep emissions low and can result in a better fuel consumption.
Just to further confuse you...there are some joint marketing initiatives around the UK with Esso teaming up with Tesco and BP with Marks and Spencer. In these cases, the "proper" version of the oil companies fuel is supplied.
Phew..hope all that reads OK and answers the questions.
Paul (AKA The Sad Fuel Geek)