i see some of you have gutted the cat. i was going to do the same, but my stock cat has a bend in the exhaust pipe as it exits. i don't really want to cut and weld anything so how did you gut yours? did it affect o2 at all?

 

I would just take the cat off and have the 0-2 sensor tapped into the pipe rather than gutting it....it would be even less restrictive.

 

I tried to gut the cat on my truck and it ran like crap. Not sure if it was related to o2 sensor. I do know that if i have any kind of exhaust leak b4 the muffler
i can forget about any kind of gas mileage and also a lack of power. My thinking is that it needed the back pressure to run good.

Had the same problem in a 98 GM v8. when i knocked out the honey comb it ran, just not well.

Local custom truck mechanic told me if i want to pull it off i need to buy a HP chip for the computer???????

 

Haven't gutted the cat on the ram... I had two gutted cats on true duels on a '00 dakota 4.7l and it seemed like it did more for WOT sound than it did for real performance

 

Gutting it will cause issues with your truck if you have an o2 sensor behind your converter. You will have to get an o2 sensor simulator to keep the computer happy. And IIRC, any truck 98 and newer should have a post-converter sensor.

 

I gutted the cat on my 98 when it went bad on me. I didn't notice any difference in performance or mileage, but it sounded like crap and I didn't pass emissions.

 

normally ... if you want to modify the cat system... to see performance or any gains... besides noise.. a highflow cat is the way to go... i just got one... waiting on some more parts and the ram is getting an enitrely new exhaust system.... headers back

 

I cut mine off and welded a Y pipe in its place, couldn't really tell a change in power or mileage. Its has never made the computer trip a code at all and runs great, just like it did before i took it off.