This paper describes a study in which approximately 100 1975 and 1976 model-year, vehicles were tested to measure the regulated exhaust gas emissions and particulate sulfate emissions. Each vehicle was tested three times over a period of approximately 11 months. All tests were conducted with the owner's brand of commercial fuel which was analyzed for sulfur and lead concentrations, Reid vapor pressure, distillation and API gravity. Average sulfate emissions during congested freeway operation are 13.6 mg/mi. There is a significant reduction in sulfate emissions during the first 12,000 miles of vehicle operation. Most vehicles equipped with air injection emit comparable levels of sulfuric acid whether the catalyst is pelleted or monolith. The only exception are vehicles equipped with Matthey-Bishop catalysts which are substantially lower. Based on FTP results there is a definite increase of CO emissions within the first 12,000 miles of operation. Deterioration of HC emissions during the first 12,000 miles of operation is only seen in classifications: vehicle/catalyst classifications vehicles equipped with pelleted catalysts without air injection and Fords equipped with Engelhard monolith catalysts and air injection. No significant changes are seen in NOx emissions during the first 12,000 miles of operation.

  • Corporate Authors:

    Society of Automotive Engineers (SAE)

    400 Commonwealth Drive
    Warrendale, PA  United States  15096
  • Authors:
    • Herling, R J
    • Gafford, R D
    • Carlson, R R
    • Lyles, A
    • Bradow, R L
  • Publication Date: 1977-3

Media Info

  • Features: References;
  • Pagination: 13 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00158328
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Report/Paper Numbers: SAE 770062 Preprint
  • Files: TRIS
  • Created Date: Oct 13 1977 12:00AM