Removing of Catalytic Converter

[ALBundy]

I removed it on my previous e36 and subsequently put it back. It wasn't good to drive.

 

[aliris]

Just to add.
for a newer e39..(facelift model) the catalytic converter in incorporated into the manifold...I doubt that the picture on the first page of this thread is pointing to the right parts. It looks more like mid silencer to me..as you can see in M54 engine, you have pre cat and post cat O2 sensors.

Just my 2 cents

 

[aliris]

here is the pict of cat conv for M54

 

[evilnickwong]

I removed it on my previous e36 and subsequently put it back. It wasn't good to drive.

Why wasn't it good?

Did you just remove completely and replace with piping or replace with a resonator/etc?

 

[ess530i]

i replaced the cat on my stock e60 header (yes, the cats are on the headers) with straight pipes and it doesn't drive very well. lost the low end torque but gained some at mid-high rpm range. it is very similar to removing the center resonators. car is auto and it somehow cause the gbox to shift early thus losing even more low end pickup. am now shopping for a new set of headers... any recommendations?

 

[aliris]

I believe that the backpressure from the restrictive cat converter in the header/manifold and the resonator plays a part in how the auto gearbox behave. One of the option is to reinstall the straight thru pipe and get somebody who can tweak your auto ecu or get a high performance cat with the like from miltek or magnaflow