Evaluation of the Yamaha lean combustion engine system: emissions and fuel economy

Book · Tue Jan 01 04:00:00 EST 1974

OSTI ID:7190516

Federal driving cycle emissions tests were performed on a 1975 Toyota Corolla and Toyota Celica which were equipped with Yamaha lean combustion engine systems. The carburetor and cylinder head of the Yamaha system incorporate a number of proprietary modifications to facilitate lean operation (air/fuel ratios of between 17:1 and 18:1). The exhaust manifold is insulated to elevate temperature and thereby promote hydrocarbon and carbon monoxide oxidation, with exhaust gas recirculation also being employed. The Yamaha Corolla demonstrated hydrocarbon levels below the 1976 statutory emission standards, while CO levels were 12 percent above these standards. Nitrogen oxide levels were consistently below the 1975 interim emission standards. The Yamaha Celica easily met the 1975 vehicle certification levels. Several driveability problems were encountered with both cars, and there were fuel economy penalties when compared to current 1975 model vehicles achieving similar levels of pollutant emissions. Aldehyde emissions from the Yamaha lean combustion engine system were lower than present production cars. (Air Pollut. Abstr.)

• OSTI ID: 7190516
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AIR POLLUTION
AUTOMOBILES
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
CONTROL
ECONOMICS
EMISSION
ENGINES
ENVIRONMENTAL EFFECTS
EXHAUST GASES
GASEOUS WASTES
HYDROCARBONS
INTERNAL COMBUSTION ENGINES
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION
VEHICLES
WASTES