How has Shell tested the formation of gunky build-up?
By using a special test vehicle, in which one half of the engine runs on Shell gasoline, and the other half runs on low-quality discount gasoline, two gasoline products were tested in a single engine under identical conditions. In addition, an open-road test was performed using two identical cars, one filled with Shell gasoline, the other filled with low-quality discount gasoline. The cars set out on a 5,000-mile journey to prove the difference in fuels. The results of both the engine and road tests were that the engine using low-quality discount gasoline built up more gunk than the engine using Shell gasoline.
