Regulatory

In 1995, the U.S. EPA Clean Air Act defined a minimum level of deposit control performance for all bulk gasoline sold in the United States. This is known as the U.S. EPA LAC (Lowest Additive Concentration) requirement. At the time, automobiles predominantly had port fuel injection (PFI) engines where performance was driven by cleaning the intake valves and injectors. In 2005, global OEMs adopted the use of a higher performance level of gasoline additive know as TOP TIER™. This provided an opportunity to differentiate and offer a high-end product to drivers and OEMs demanding optimum performance and efficiency.

Car Parc Evolution

Over time and increasing demands for lower emissions and higher fuel economy, OEMs shifted focus to gasoline direct injection (GDI) engines, where the fuel is injected directly into the combustion chamber. Fast forward to today, GDI engines have become the dominant injection type used by OEMs, making up ~ 40% of the car parc and >80% of all new car production in North America*.

TOP TIER™

While automobile engines have changed over time, gasoline performance testing hasn’t. So, in February of 2025, TOP TIER™ upgraded their fuels standard spec to TOP TIER+™, aimed at providing more protection for GDI engines. In addition to the existing spec, TOP TIER+™ adds a GDI injector performance test and two no-harm tests: particulate emissions and preignition. This new standard emphasizes advanced chemistries, enhanced engine cleanliness, and modern engine protections.

UltraZol® GA9110 Series has been formulated to clean and keep away fuel system deposits for both PFI and GDI gasoline engines.

Cleans and protects critical fuel system components
Does not harm particulate emissions
Does not cause preignition
Flexible performance cascade
Solutions for varying temperature requirements

* Source: Lubrizol Analysis