The 240 exhaust system (non- turbo) seems two have two mufflers downstream from the cat converter. Some years ago the connection at the inlet to the muffler which sits behind the rear bumber did break and I did not notice a significant increase in the noise I replaced the connecting pipe which goes under the rear axle .

Now the female connection to the first muffler is broken. What would be the increase in noise if I was to replace that first muffler by an equivalent length of pipe, properly suspended to the frame .

Would there be a detrimental effect on the engine, the performance or the effectivenes of the catalytic converter if such a substitution took place because of changes in back pressure or other reasons ?