07/02/03 1 ARB – Exhaust Emissions – Tier 3 Small Off-Road Engine Workshop – July 2, 2003 EMA / OPEI Engine Manufacturers Association / Outdoor Power Equipment Institute Clean Air Act Committee

07/02/032 ARB – Exhaust Emissions – Tier 3 Current production systems -- what do they achieve? Southwest Research test program -- what does it demonstrate? ARB’s current proposal -- what will it require for the air-cooled engine?

07/02/033 Small Off-Road Engine -Production Catalyst Systems International Catalyst System – B&S –20-30% HC+NOx Efficiency at 0 hrs –7-10% HC+NOx Efficiency at 125 hrs –Marginal CO Conversion

07/02/034

5 Small Off-Road Engine -Production Catalyst Systems Tecumseh TVM in 3 Vertical L-Head 15% HC+NOx Efficiency at 0 Hours Tecumseh H in 3 Horizontal L-Head 29% HC+NOx Efficiency at 0 Hours

07/02/036 Southwest Research Test Program –Six engines equipped with high-load three-way converters –Three engines equipped with non- integral systems –Exhaust emissions and temperatures measured at 0 hours and after test stand operation –No noise abatement or measurement

07/02/037

8 SwRI’s Catalyst System

07/02/039 Muffler Skin Temperatures

07/02/0310 Temperature Measurements at SwRI –Temperature measurements at SwRI are incomplete –Temperature measurements at Briggs & Stratton indicate temperatures at 1150 F, not 770 F –Southwest Research should conduct additional temperature measurements

07/02/0311 SwRI – Honda GCV160

07/02/0312

07/02/0313 SwRI – Honda GCV160

07/02/0314 SwRI –Honda GCV160

07/02/0315 Conclusions -- SwRI Test Program –High-load catalysts will require additional thermal management More hardware More horsepower –Other requirements related to after-treatment: Noise: new, larger mufflers Lean fueling: accelerator pumps, auto-choke and warm-up feature –New base engine for walk-behind market in California –New packaging/envelope challenges for equipment manufacturers

07/02/0316 Preliminary and Partial Cost Estimates –Approximately $60 for exhaust only (does not include evap) –Cost estimates do not include: Warranty, testing or R&D OEM assembly and other costs

07/02/0317 Summary –Can small engines achieve high conversion efficiency in the laboratory? –Yes, but…

07/02/0318 Summary Production for California will require complex changes at higher costs: Three-way high-load converters Noise and thermal management Major fuel system changes New, larger base engine New packaging solutions