Muffler for internal combustion engine

An improvement in a muffler for an internal combustion engine, where the muffler has a casing with a pair of end walls interconnected with first and second sides and with an inlet opening on one end wall and an outlet opening on the opposite end wall, said improvement including in combination:

• a first exhaust pulse splitting means located in said casing near said inlet opening a first predetermined distance from said one end wall for splitting exhaust flowing into said casing from said inlet opening into separate first and second parallel flowing exhaust streams directed toward said first and second sides, respectively;
• a second exhaust pulse splitting means in said casing in the path of said first parallel exhaust stream a second predetermined distance from said one end wall and located nearer said first side than said second side for further splitting said first exhaust stream into third and fourth parallel flowing exhaust streams;
• a third exhaust splitting means in said casing in the path of said second parallel exhaust stream a third predetermined distance from said one end wall and located nearer said second side than said first side for further splitting said second exhaust stream into fifth and sixth parallel flowing exhaust streams, said third predetermined distance being greater than said second predetermined distance, so that said second exhaust pulse splitting means is located nearer to said first exhaust pulse splitting means than said third exhaust pulse splitting means is located to cause said exhaust streams from said second and third exhaust pulse splitting means to be out of phase with one another;
• and
• combining means for mixing together said third, fourth, fifth and sixth exhaust streams from said second and third exhaust pulse splitting means for supplying exhaust to said outlet opening.