1991 240 B230 engine. I'm wanting to get a better understanding of the two mufflers on my 240.

On my car I have the cat converter and that pipe leads into a smaller tube shaped muffler and that one leads through some bends to the main larger muffler that sits under the trunk.

My question is what is the reason for the smaller muffler?

I ask because I decided to try to figure out why my exhaust flow seemed so low compared to another 240 which was considerably older. The 84 240's flow out the tailpipe was at least twice the amount of flow at idle compared to my 91's. Different engine perhaps?

So, I decided to remove the exhaust from the cat's triangular flange and inspect the cat suspecting it was clogged or at least partially clogged. Naturally the three bolts wouldn't budge and one snapped off when I was trying to loosen them...I ended up using a reciprocating saw to cut off the bolt heads.

What I found is the cat was completely empty... (at least now I know) but now before I go about re-installing everything I would like to know more about the smaller muffler...It feels light and I have never heard of mufflers clogging but I suppose anythings possible.

So can anyone shine some light on the smaller muffler for me?