For many years, Ethyl Corporation engineers have conducted research into engine operation at lean air-fuel ratios. They were interested in lean-mixture combustion because of the inherently low emissions and good fuel economy that are possible with a properly controlled lean engine. Some of their recent research efforts have been to demonstrate the potential of lean-mixture control techniques to meet the future emissions standards of the European Economic Community. Part of the recent work at Ethyl has been with vehicles that use small high-performance engines, on which significant reductions in emissions have been achieved. The Emission Control Technology Division, consistent with its continuing interest in the evaluation of advanced automotive emission control technology, requested a vehicle for testing, and a BMW 2002, equipped with Ethyl's Turbulent Flow Manifold induction system, was made available.