Comparative Test Analysis of Exhaust Noise of OEM, HPLPM and Free Flow Under Three Test Conditions

Abstract

Abstract This research aims to measure OEM, HPLPM and Free flow mufflers under several noise level testing. In this study, the factory-installed exhaust was replaced with a free-flow type and HPLPM exhaust. The research employed a quantitative method with an experimental approach. Testing was carried out under three different vehicle conditions that correspond to their usage: normal condition, exhaust condition, and acceleration condition. Each type of exhaust was tested three times for each testing condition. Subsequently, the collected data were analyzed and compared against the established quality standard in Indonesia, which stipulates that the noise level must not exceed 90 db. Based on the average noise levels produced by the free-flow exhaust type, it was found that under normal vehicle conditions, the average noise level was 28.08% higher compared to the OEM exhaust type. Under exhaust conditions, the free-flow exhaust type resulted in an average noise level 23.13% higher than the OEM type. During acceleration, the free-flow exhaust type generated an average noise level 14.54% higher than the OEM type. Employing the HPLPM exhaust type under normal vehicle conditions yielded an average noise level 25.9% higher than the OEM type. Under exhaust conditions, the HPLPM exhaust type led to an average noise level 21.2% higher than the OEM type. Finally, during acceleration, the OEM exhaust type produced an average noise level 0.03% higher than the HPLPM type. Based on this data, HPLPM can reduce noise levels better than free flow muffler. At the higher RPM HPLPM can produce almost the same noise as the OEM type.