Bought a Pittsburgh Muffler without directions for airflow.
I got a PP muffler from the walcott IA I80 TA. On this muffler there was no arrow to show airflow. I know they have a couple different models. This one on the outside both sides look identical. On the inside the middle is open one side is straight through with holes all the way down, the other side has holes part way down and then tappers in bout a 1/4 inch and is solid till the middle where it tappers back out b4 the break in middle.
the ends were are identical on the outside the only diffence is the inside one end is tappered in about a 1/4 inch
It didnt have the flanges (that i know of anyway) the inside had holes but was smooth besides that.
Is this a good question?