Fuels

Fuel combustion in an engine is at its most efficient when the precise amount of air and fuel are mixed at the right time. With some conventional fuels, deposits may form over time on the back of the inlet valves. This can lead to delays in the required fuel charge entering the engine and a poor mix of fuel and air, reducing an engine's efficiency. To combat this, Shell developed a fuel economy formula, which is now used in our unleaded petrol range, preventing the build-up of these deposits in the first place

In the case of engine friction, losses can occur whenever two moving solid surfaces come into contact with each other. In most parts of the engine friction is minimized using an appropriate lubricant, however the top piston ring and cylinder wall is very difficult to lubricate effectively. Consequently this area of the engine is vulnerable to friction losses. Here again, the fuel economy formula can help as it has been created using Shell’s Synthetic Viscous Friction Improver, designed to reduce friction in this critical part of the engine, helping to improve its efficiency.

The formula wasn’t a recipe easily reached, but is based on decades of research in which our scientists identified all the key areas where fuel can impact on the engine. And using this knowledge, they developed the formula. During development, the formula underwent stringent tests both in the laboratory and in road conditions. The test results were then independently reviewed by the Society of Automotive Engineers (SAE) and published as an SAE paper, before the formula was finalised and finally released to petrol stations as New Shell Unleaded, Shell Unleaded 95 and Shell Premium Unleaded petrols.

Our Unleaded range with the Fuel Economy Formula should give drivers more kilometres to the tank, but whether it does or not, also depends on driving style, weather conditions and other factors. What you can do before and during driving to improve your fuel economy.