１９８６年度国産乗用車のオクタン価要求値調査結果

The Sub-Committee of Octane Number Requirement (ONR) of the Japan Petroleum Institute conducted 1986 ONR Survey to estimate maximum ONR distributions for 1986 model cars on the road by use of maximum ONR data compiled from 215 test cars. The maximum ONR data were determined by means of the low speed test method using Primary Reference Fuel (PRF) and mixed type of unleaded Full Boiling Range Reference Fuel (FBRRF). We summarize below the results of 1986 ONR Survey together with pertinent information on test cars, test fuels, test method for ONR measurement and calculation procedure for maximum ONR distribution determination.<br>Maximum ONR of 215 test cars were scattered from 79.0 to 97.0 RON as tabulated in Tables 5 and 6. Using those data, maximum ONR distributions for 1986 model cars on the road were calculated.<br>Fig. 1 and Table 7 indicate that maximum ONR distributions for 1986 model cars on the road determined by PRF were 88.5 and 93.0 RON at 50% and 90% car satisfaction levels, respectively. These ONR distributions for 1986 model cars were similar to those for 1985 model cars as shown in Fig. 2.<br>This decreasing tendency has been continuing since 1983 as indicated in Fig. 3.<br>Regarding maximum ONR distributions by engine displacement, 1, 301-1, 600cc engines prone to show higher maximum ONR as summarized in Table 9. More than 91% out of 215 test cars showed maximum ONR at the wide open throttle acceleration condition as indicated in Fig. 4.<br>ONR data were collected on 215 Japanese passenger test cars (14 models includuing 112 cars equipped with automatic transmission). The test cars and their engine types are shown in Table 1.<br>For 1986 ONR survey, PRF and FBRRF were used as reference fuels. The ratio of blending stocks for FBRRF and properties of each blending stock are shown in Tables 2 and 3, respectively.<br>About 90% of maximum ONR data were determined on the nine chassis dynamometers of the participant companies and the remainings were measured at the test track of the Japan Automotive Research Institute.<br>Maximum ONR data were measured by means of JPI Standard Method 6S-6-84 (the low speed test method) which covers trace knock determination in the range from 1, 000 to 4, 000rpm engine speed during the acceleration condition at the highest gear position. The acceleration technique is summarized in Table 4.<br>118 out of 215 ONR data were obtained with 1986 model test cars. The remaining 97 ONR data were of 1985 model test cars which are still on the market as 1986 model cars without full model change.<br>Maximum ONR distribution for the 1986 model cars on the road was determined by means of the JPI Standard Method 6S-7-84 using ONR data of test cars.