heres the test octane test
Previous fuel economy formulations have been solely based on inlet system deposit control over extended mileage using detergent additives.
This new additive formulation combined with the new Shell Efficiency Improver component works by lubricating where normal engine oils can’t easily reach. This can help engine components to turn more freely, resulting in more of the fuel’s energy being made available to drive the wheels.
This helps you get more out of every drop of Shell FuelSave Unleaded and saves you up to 1 litre per tank* at no extra cost.
Getting to this stage was a welcome challenge for our scientists, who relentlessly tested the fuel in their lab as well as on the road so that each time you fill up, you save.
Over 5,000 miles were driven in the series of on-road demonstrations have been carried out in a range of cars and engine types. Tests were carried out at a third party testing centre using an industry recognised Fuel Economy Drive Cycle. Each vehicle was tested 36 times over a 6 month period and over 5,000 miles were driven in the series of on-road demonstrations.
So, save up to 1 litre per tank* with Shell FuelSave Unleaded – head to your nearest Shell station today.
*Based on a minimum tank size and fill up of 50 litres. Comparison between a standard gasoline and that same standard gasoline containing our instantaneous fuel economy formula. Actual savings may vary according to vehicle, driving conditions and driving style.
so you save 1 litre in a 50 litre tank, these tests where done on the roads so by a person and that person wouldn't be able to drive the same on each road exactly the same or even in the same conditions
so id say a placebo effect
Ash