The TOP TIER™ Detergent Gasoline Performance Standard describes the test methods used and the performance requirements that retail unleaded gasoline must meet to be licensed as TOP TIER™. Additive Companies conduct the testing on a given additive package and submit the results in order for the additive to obtain approval for use in TOP TIER™ Detergent Gasoline products. The fuel's impact on engine performance is measured via:
- Intake valve and combustion chamber deposits from fuel additized
at the TOP TIER™ treat rate in comparison to base fuel containing no additive
using ASTM D6201.
- Valve sticking tendency of the test fuel with a high level of
the TOP TIER™ Detergent Gasoline using either the 1.9 L Volkswagen engine
(Wasserboxer according to CEC F-16-T-96) or the 5.0 L 1990-95 General Motors
V-8 engine (Southwest Research Institute IVS test).
For more details download the TOP TIER GASOLINE PERFORMANCE STANDARD