Muffler is accountable for noise decrements of an engine and due to this it creates backpressure. Primary objective of this work is determination of exhaust back pressure of muffler using computational fluid dynamics (CFD) and by using experimental validation. Main focus of this work is to reduce the backpressure created in the muffler. Exhaust back pressure is one of the important factor which is generally scrutinized by the automotive manufactures to make sure that their engine gives a better performance.