So i just got a borla muffler installed, but its not as loud as i would want it. The durango has 3 catalytic converters. one right after the right side header one right after the left header.(This is where the o2 sensors are located around those two cats) and then the main fatty cat thats in the mid pipe before the muffler. So what i want to do is remove the last cat before the muffler so more of the sound comes out. i will cut out the cat and replace it with a 2.5 inch pipe and then clamp both sides together using a band clamp like this one. hopefully the sound will be louder and the car will be a little more free flowing. there still will be back pressure because of the 2 cats that still remain and the piping is still all stock and wiggly causing more back pressure. and when i go get smogged ill just bolt the cat back on. Nothing really controls this last cat. the front o2 sensors that are in front of the 2 pre-cats are for air/fuel mixture. and the ones after the pre-cat but before the main cat are to make sure the 2 cats are working correctly. so the third cat is not being watched by any electronics. so i should be fine ya?

thoughts? comments?

 

yes you should be fine, the only reason to put it back on for smog inspection is if they sniff the tailpipe where you live, they dont here, they just check the obdII port

 

ok cool. thank you

 

question - how MUCH louder do you think it would be by removing one cat and still having 2 left? my exhaust currently is maybe like medium loudness. Its a borla muffler so it has bass but its not anything really loud.

 

Your Durango will NEVER pass Cali inspections. Why mess around and end up paying a $1000 to get it back like it is supposed to be? The Durango cats flow fine as stockers, and often better than hi-flo/hi-price cats. You obviously do not understand what a Cat does. It superheats the exhaust gases to burn them off more cleanly. There is little to nothing in there to affect sound. You are wasting your time and energy not to mention the Durango is designed for a certain level of backpressure from the cats to run correctly.

There is a difference between obtaining a performance sound from the exhaust and a redneck sound. When someone watches you pass because they are impressed with the sound, you have obtained the performance level. When they look at you like a jerk off for waking up their baby, well... Kentucky will always consider you a resident. They marry their cows and their sisters in Kentucky too. Dumb rednecks.



IndyDurango

 

lmao funny. but i dont plan to go get smog checked with the cat out. which is why i said id bolt the cat back on when going to get smoged. I just want more sound. and im not so sure about the no affect in sound. i see tons of videos of people taking one cat out and changing the sound. The D will still have 2 cats left to "super heat" the exhaust to burn it off. If you look at subaru wrx turbo back exhausts a lot of them come with deleting one of the 2 cats on the down pipe because it does change the sound. theres not as much material in the way to absorb the sound waves so you dont get as much of that whooshing sound.

and my exhaust to begin with isnt that loud i have a borla muffler, its not going to sound like a unmuffled tractor lol.

 

California is the nastiest state with emissions as Indy stated. I would not mess with the catalytic converter unless you live in another state. My Demon had a large pipe in the truck with four smaller hoses in it that came off each corner of the fuel tank for California emmissions. I think it recirculated the fumes in an early EGR form. Soon all states will be as strick as your state,
FF
FF

 

I understand the emissions part but what about the eng leaning out with not enuogh back pressure? I woul like to delete my muff.

 

you should be fine deleting the muffler.

 

yea but i will be putting the catalytic converter back in when i get smogged etc. if i decide to do it. should take 10 minutes to get under the car and swap from a pipe to the cat.