Comparison of leaded and unleaded aviation gasoline based on engine performance

Abstract

The aim of this study is to compare the performance of spark ignition engine using leaded and unleaded aviation gasoline. The leaded and unleaded aviation gasoline used for this study contains the same Motor Octane Number (MON) of 91. The lead content in the existing aviation gasoline is a harmful substance to human health. The concerns regarding this matter resulting the development of more unleaded fuel as a replacement for the leaded fuel. Three parameters to be considered while carried out the study are Brake Horse Power (BHP), Exhaust Gas Temperature (EGT) and the Brake Specific Fuel Consumption (BSFC). The performance test is conducted using auto engine dynamometer to measure the listed parameter produced by test engine, Lycoming O320. Based on the results, the test engine using leaded avgas able to produce power 4.66% higher than unleaded avgas at the rated engine speed, 2700 RPM. But, the data for EGT shows that the unleaded avgas is 1.39% better than leaded avgas. For fuel consumption, the unleaded avgas required 27.46% more fuel than leaded avgas at the same engine speed, 2700 RPM. Overall, the leaded aviation gasoline provides better engine performance than unleaded gasoline.