There was something about this on the One Show this week. They said that all petrol comes from just a handful of manufacturers and the specification is the same for all brands and supermarkets buying power, lower margins together with getting you in the store to buy your groceries is the reasons they are cheaper. They interviewed QA inspectors who said it was all the same and manufacturer management.
They then went on to say that then the branded suppliers may then put their own additives in to clean the engine, burn more efficiently etc.
I have used both branded and supermarket and found on the diesel that BP was a little smoother than Sainsburys and a lot smoother than Morrisons which I stopped using and gave about 3 more mpg. But if I used Sainsburys and Redex the results were similar and works out cheaper.
On petrol I run my Dolomite on Sainsburys Super Unleaded with a lead and petrol stabiliser additive and it runs well. Dolomite engines vary, some can run on unleaded but mine cant. However when I have used Esso, BP etc it runs much better and has more power. My Volvo recommends using Super Unleaded for better performance and economy and standard unleaded is ok to use. I use both but find that if I use Sainsburys unleaded I get the bad egg smell. Had every thing checked out in case and was told it was the fuel. Their super unleaded, which is in now in the tank is better the car runs and gives better economy by a couple of mpg but still gets the odd whiff of bad eggs. If I use BP from around the corner the standard unleaded runs as well as the Sainsburys super and costs about the same or a little more and no smells so that's what I use mainly. The Super duper stuff they sell does improve on this and I can tell its in but the cost puts me off it.
|