Ignition Timing Impact on the Performance of an Old Technology Vehicle Fuelled by Ethanol/Petrol Blends

The scope of this work was to study the impact of the ignition timing on the engine’s performance on an old technology vehicle fuelled by ethanol/petrol blends. Many previous studies have been published on the subject, but most of them were carried on SI engines using bench dynamometers. In this work, a 1.3 L Ford Escort equipped with a carburettor and without a catalytic converter was tested on a chassis dynamometer. Blends with ethanol concentrations of 10%, 20% and 50% per volume were used and the results were compared with the reference LRP fuel. All tests were performed at three different constant speeds of 30, 50 and 90 km/h, under full load with wide open throttle. Torque and rpm of the engine were recorded by the chassis dynamometer’s software. The fuel consumption was measured by means of the gravimetric method. All measurements were taken at three different settings of the advance angle, at 0°, 4° and 12° BTDC. For the evaluation of the results, the combustion chamber’s mean pressure and the lambda value were calculated from the available recorded data. Changing the ignition timing, while using the blends E10, E20 and E50, had the same effect on the power as the reference fuel E0. By advancing the ignition timing, an increase of the mean pressure in the combustion chamber was observed, resulting in an increase of the torque and the power. A reduction of the specific fuel consumption was also measured as a result of advancing the ignition timing.