Hey guys,

I want to remove the cats n resonator to get more growl out of my gt haus on my 535i.
Is removing cat and resonator a simple job??
Do i need to go to a specialized muffler shop?? Or just a local shop can do the job??

Thanks

 

Cut the pipes before /after the cat & the reso. Weld a pipe in its place. Make sure to use same diameter piping to link to the existing pipes. I believe that it is the easiest way.

Beware of local regulations to noise level; polution by not having the cat, MOT..

I wanted to do it too..but mine is a diesel..Do not know if it will have same growl made by petrol engines. Anyone have ever tried it on a diesel engine?

Good luck..

 

how will you deal with the O2 sensors not being plugged in?

 

Im talking about the secondary cats. I believe that one doesnt have the 02 sensors.

 

This is true (at least on my 08 535i) i have a total of 4 cats. the first two cats have the sensors the second two cats (secondary) have no sensors whatsoever.

 

Just leave it OEM and don't mess with it or you'll regret it. It'll waste your time and money...unless you're in your 20's and NEED to have a sound to make you feel like you purchased a powerful exotic sports car. It'll still be/sound weak either way.

 

Big thumbs down to this! Do what makes you happy with your car. I removed my cats and i absolutely love the new sound/grumble. I did however ensure my setup allows me to put my cats back on should i want a quieter ride or need to accomplish a smog test. If sound is what your after and it will make you smile when you are driving YOUR car then i say go for it!

 

If you need a sound to make you smile....

 

To each his own....

 

do whatever makes you happy mate, the only thing i would like to add is get a remap once done, changing how the engine breathes in this way throws the fuel and ignition timing out which could potentially cost you power and more in fuel