Enhancing the heavy load performance of a gasoline engine converted for LPG use by modifying the ignition timings

摘要: Abstract This paper presents the results of experiments conducted on a spark-ignition (SI) engine fuelled with liquefied petroleum gas (LPG) by varying ignition timing at excess air coefficients 1.0 and 1.3. Experiments were carried out wide open throttle (WOT) position speed 4300 rpm aiming to determine lean operation performance an when LPG full load. Performance parameters, namely brake power, brake-specific fuel consumption (BSFC), thermal efficiency exhaust emissions such as unburned hydrocarbons (HC), carbon monoxide (CO) nitrogen oxides (NOx), studied. It was shown that advancing improved LPG-fuelled SI for higher than 0.8. The highest power lowest BSFC obtained modified coefficient 1.0. In general, timings caused increase in HC NOx emissions, while effect CO negligible.