Intake and exhaust systems that harness the pressure pulses and resonances inside the various passages and chambers of the intake and exhaust manifolds . In this way they increase the flow of intake charge into and out of the combustion chambers. Although the exhaust port must be a smooth as possible, the intake port must not because the fuel must churn and mix with the air.
TUNED EXHAUST
Meaning of TUNED EXHAUST in English
English dictionary of automotive terms. Английский словарь автомобильных терминов. 2012