The Federal Government currently determines light-duty vehicle fuel economy and emissions on the twin small-roll dynamometer. The geometry of the dynamometer-vehicle system is one which cannot be duplicated under actual driving conditions because only the rear tires are placed on the dynamometer and the surface upon which they are placed is curved. Recently, questions have been raised as to the validity of the assumption that two tires on the dynamometer equals four tires on the road with regard to all tire construction types. However, it has been suggested that when radial tires are operated on the twin small-roll dynamometer they exhibit higher rolling resistance than the other construction types under the same conditions. Lack of information prompted an in-house investigation into the effects of the twin-small-roll dynamometer on tires.

  • Corporate Authors:

    Environmental Protection Agency

    Standards Development & Support Branch, 2565 Plymouth Road
    Ann Arbor, MI  United States  48105
  • Authors:
    • Burgeson, R N
  • Publication Date: 1978-3

Media Info

  • Pagination: 69 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00313514
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: EPA-AA-LDTP-77-4 Tech Rpt.
  • Files: TRIS
  • Created Date: Jun 26 1980 12:00AM