Fuel Cat not only optimizes burning of fuel, but also keeps the engine clean by leaving no unburned fuel that can then turn into carbon monoxide, unburned hydrocarbon and free carbon (as soot) emerge from the combustion process. The unburned hydrocarbons and free carbon form gum or wax, and are loosely described as carbon deposits, which are baked hard, in the combustion chambers, onto piston crowns, valve heads (particularly the exhaust valve) spark plugs and interior surface of the combustion chambers. The piston ring can also be seriously affected and eventually become stuck in their grooves.
Fuel Cat regulates the speed and temperature of combustion which prevents micro welding between valve and valve seats; thus preventing valve seat recession.