Replacement catalysts for in-use cars

Five aftermarket three-way catalytic converters that are available in the C reek market were evaluated in terms of their conversion efficiency by insta lling them on the same car and measuring the hot emissions from each at the New European Driving Cycle and two driving cycles of short duration. The r esults show differences in the car's emission levels with each catalyst, bu t also discrepancies in repeat measurements of the three converters. The di fferences between the relevant regulations that are effective in the US and those proposed for Europe are discussed.