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A full size V8 demonstrator was developed to exhibit technology required to target LEV II emission levels. The testing involved the system integration of a vacuum-insulated catalytic converter (VICC) technology, air gap exhaust components, optimized catalyst loading and control system and calibration. The development strategy utilizes the vacuum insulation, phase-change thermal storage capacity, and cold start calibration strategy to enable the catalyst to quickly reach light-off in 6 seconds over the FTP-75. All emission testing was conducted with two LA4 preparation cycles. This approach is able to reduce the heat loss of the catalytic converter brick during a 12 hour soak period and optimize the calibration warm-up strategy to reduce the amount of emissions during the first 60 seconds of the FTP-75. The vehicle used for the demonstration was a BMW 540I application. The modifications to the vehicle were limited to the control system, engine calibration and aftertreatment.

In previous SAE papers, the initial development and testing of a vacuum-insulated catalytic converter was presented. This paper provides an update of the converter development and an analysis of potential off-cycle emissions savings. Hot vibration, cool-down, and 1975 Federal Test Procedure (FTP-75) emissions test results are provided to demonstrate the effectiveness of design improvements in greatly increasing durability while retaining performance. Using standard drive cycles and “real-world” driving statistics with a vehicle simulator (ADVISOR©), catalyst temperature and vehicle exhaust emissions of a sport utility vehicle (SUV) were predicted for 16 days of driving (107 trips, 770 total miles). Compared to the baseline vehicle with a conventional catalytic converter, the SUV with a vacuum-insulated converter produced 66% less non-methane hydrocarbon (NMHC), 65% less carbon monoxide (CO), and 60% less oxides of nitrogen (NOx).