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A cooperative cold-start and warmup driveability program was conducted by the Coordinating Research Council (CRC) in Yakima, Washington, during the fall of 1989. The program investigated the independent effects of front-end and mid-range volatility on cold-start and warmup driveability of twenty-four late model vehicles at intermediate ambient temperatures (30°F - 56°F). Volatility ranges investigated were those that may be required of future summertime fuels. Mid-range volatility (T50) was found to have a substantially significant impact on driveability, regardless of fuel-system type, while front-end volatility (RVP) was found to show a lesser but still significant effect on carbureted and throttle-body-injected vehicles. Oxygenate content/type was also a significant variable.

A study was conducted under the auspices of the Coordinating Research Council, Inc. (CRC) to assess the potential effects of gasoline octane quality on vehicle acceleration performance. Twelve participating laboratories, representing both the oil and the automotive industries, tested a total of 182 vehicles as part of the 1989 CRC Octane Number Requirement Survey. The vehicles consisted of 78 with electronic knock control systems (knock sensors) and 104 without. All testing was performed using the 1989/1990 CRC FBRU fuel series. The results showed that acceleration performance of vehicles with knock sensors was significantly affected by gasoline octane quality.

A pilot study was conducted under the auspices of the Coordinating Research Council, Inc. (CRC) to assess the potential effects of gasoline octane quality on acceleration performance, fuel economy and driveability in vehicles equipped with electronic spark control systems (knock sensors). Fourteen vehicles were tested by five participating laboratories, representing both the oil and automotive industry, on CRC unleaded reference fuels of varying octane quality (78 to 104 RON). The test vehicles included nine naturally-aspirated and five turbocharged models. The results showed that acceleration performance was the parameter most sensitive to octane quality changes, particularly in the turbocharged models. No significant improvements in fuel economy were found with increasing octane. Drive-ability was not affected by fuel octane within the commercial fuel range, but three vehicles showed degraded driveability with sub-commercial octane fuels.