Dal said:
Have a little look here:
http://www.petrolprices.com/" onclick="window.open(this.href);return false;
And register to get daily / weekly updates via email as to the cheapest petrol in your area.
yeah thanks dal some really intresting information here
Octane Numbers
Usually, there are three different octane numbers associated with all petrols. Petrol's Research Octane Number (RON) is measured under simple test conditions. Petrol's Motor Octane Number (MON) is measured under tougher test conditions and at higher engine speed and temperature.
The average of these two values is what becomes related closer to actual driving conditions. This value is known as the Road Octane Number, and is what should be used in filling stations.
Occasionally, some filling stations will confuse these different octane numbers in a bid to embellish on their octane rating claims, and advertise their fuel's Research Octane Number, which is higher than the Road Octane Number. In many European countries, the Research Octane Number is advertised on pumps, so a much higher octane value is common when travelling in certain countries
Super Fuels
Many of the large petrol companies have launched 'super fuels' - petrols and diesels that have a higher research octane level. These fuels are said to increase power in many vehicles, deliver less pollution than regular fuels and help to maintain a cleaner engine. Amongst these 'super fuels' are Tesco's Super Unleaded 99 Octane petrol, supplied by Greenergy, now sold at many stations across the UK and also BP's Ultimate 102 Unleaded which is currently the most advanced, high-performance petrol you can buy on UK forecourts.
Using Super Fuels
One of our users commented that using higher octane fuel than your engine requires actually gives no benefit and may be a waste of money. This is because virtually NO engines require 98 RON over 95, and the market for 'super' fuels seems to be based on people's misunderstanding of octane ratings and the placebo effect of filling up with 'more powerful' fuel - making motorists think their engine is running better in some way.
What do the fuel companies say then, to justify the "increased power" claims for the super grade fuels? Some companies say that while all fuels contain cleaning additives, 'super' fuels contain more or better detergents to keep the injectors cleaner than standard fuel. Others say the fuel is a few percent denser which gives slightly more power per litre. These benefits may be marginal though in comparison to the extra cost involved so it is worth ensuring that your engine will actually benefit before filling up.
Some engines actually do need higher octane fuel, such as race engines with very high compression and some turbocharged engines, such as the import version of the Nissan Skyline. Also, a few vehicles, such as the new BMW K1200R motorbike, can sense knock and adjust their engine tuning to take advantage of higher grade fuels. Another user commented that the 2004 BMW 330 also does this, according to the driver's handbook it makes 231 BHP on 98 octane and 221 BHP on 95. This ability is apparently widespread amongst German performance cars using Bosch / Siemens electronic engine controls
after reading this
i think i will use normal unleaded untill my puma is remapped to use 99 ron and if my injectors seem clogged simply use a bit of injector cleaner