Cat and resonator delete and still not much rumble...




If there was engine vibration, it could be due to engine mounts or, since the exhaust sound is not what you expected, defective or partially blocked/clogged primary cats.
You didn't mention it, but the vibration/drone should have increased with the removal of the secondary cats and resonator.
My 400E had collapsed mounts and the engine would dance doing above test. Felt vibrations through wheel and pedals, esp at lights in gear. New set of Lemforders and it was quiet and vibration free until the day I got the CLK to replace it.




