Effect of local airflow restriction in the intake system on the characteristics of a naturally aspirated spark-ignition engine

One of the most important elements influencing the functioning of internal combustion engines is the intake system, whose task is to supplycold, fresh and filtered air to the combustion chambers of the engine. So far, the capacity tests of the intake system have focused on the appropriate selection of its geometry and diameter, which had a direct impact on the airflow rate, and thus on the performance of the vehicle. In this article, the focus is on conducting research consisting of placing the airflow restriction element in a specific locationin the intake system of a naturally aspirated spark-ignition engine. After the necessary preparations, authors made measurements of the engine performance (power and torque) and airflow rate in the intake systemvia original MAF sensor mounted in intake system and Chassis Dynamometer Interface via OBD protocol. After the engine parameters were measured, the test results were compared with the reference characteristics obtained during the measurements prior to the modification of the stock intake system. The article is crowned by conclusions based on the results of the measurements.