I am replacing my exhaust soon and I have a few general questions. First, if I'm not mistaken the stock pipe going into the cat from the manifold is 2.5" and the connection from cat to muffler is also 2.5"? Then the output of the muffler is 2.25" and the piping is the same.

If I get a high flow spin cat + flowmaster 44 muffler + tail pipe with all 2.5" measurements, will I have any problems attaching to the existing pipe? I will do it myself with just clamps and some sealant. No welding skills and plan to use a sawsall or grinder as needed.

Would anyone recommend I just avoid the tail pipe and just drop it down at the axle?

The manifold will be replaced after this project, as well as the upstream O2 sensor. Only things I do not plan on replacing is the downstream O2 sensor and the pipe between the manifold and cat.

Thanks

 

I tried to put a 2.5" 40 series on my Cherokee and it was close but no cigar. It was looser than a slip fit would have been, so I'm guessing the outlet of the cat is a little smaller than 2.5". I do know the pipe after the muffler is smaller than the cat outlet.

 

Stock muff/tailpipe is 2.25".