Accession Number : ADA130400

Title :   Octane Requirement Increase of 1980 Model Cars.


PDF Url : ADA130400

Report Date : Jun 1983

Pagination or Media Count : 42

Abstract : Octane requirement increase (ORI) was determined for 120 1980 model cars operated on unleaded gasoline. All ORI values were determined from the increase in maximum octane requirements irrespective of whether requirements were obtained at full- or part-throttle. At 15,000 miles, the mean ORI for all cars with full boiling range unleaded (FBRU) fuels was 5.1 Research octane numbers, 3.5 Motor octane numbers, and 4.3 (R+M)/2 numbers. At 15,000 miles, the mean ORI for 89 cars with full boiling range high sensitivity unleaded (FBRSU) fuels was 5.0 Research octane numbers, 3.3 Motor octane numbers, and 4.1 (R+M)/2 numbers. At 15,000 miles, the mean ORI for all cars with primary reference fuels (PRF) was 3.9 octane numbers. Compared with 1979 models (109 cars), the mean ORI for all cars in the 1980 program with FBRU fuels was 0.3 RON lower and 0.1 mon lower. Neither difference is statistically significant. In general, the mean ORI with FBRU fuels has not changed appreciably from the 1975 through 1980 model cars. ORI decreases about 0.3 octane number per octane number increase of initial octane requirements; this relationship is statistically significant.

Descriptors :   *Passenger vehicles, *Additives, *Gasoline, Requirements, Road tests, Test methods, Comparison, Specifications

Subject Categories : Fuels

Distribution Statement : APPROVED FOR PUBLIC RELEASE