Catalytic Converters

The engine management system provides accurately metered quantities of fuel to the combustion chambers to ensure the most efficient use of fuel and to minimize the exhaust emissions. A threaded boss is located on each manifold, between the starter and the main catalysts and on the pipes between the catalytic converters and the front silencer to house the pre, mid and post catalyst HO2S (heated oxygen sensor) 's. The pre catalyst HO2S 's primarily control the engine fuelling, while the mid-catalyst and post catalyst HO2S 's are primarily used to monitor the conversion efficiency of the catalytic converters and perform further trimming of fuelling. The engine management system monitors the sensors and uses the information to further improve the fuelling and exhaust emissions.

In the catalytic converters, the exhaust gasses are passed through honeycombed ceramic elements coated with a special surface treatment called 'washcoat'. The washcoat increases the surface area of the ceramic elements by a factor of approximately 7000. The washcoat is impregnated with palladium and rhodium, which are the active constituents for converting harmful emissions into inert by-products. The palladium and rhodium convert carbon monoxide and hydrocarbons into, amongst other things, carbon dioxide and water.