hollowing out the 3rd cat

[Antoine08]

i keep going back and fourth about this mod.

Same here. Don't want to end up popping a code or run to lean

[Cliff14Denali]

I did it with no issues....if you have stock cat back or just replaced the muffler only, you won't even notice much of a difference.

[2014MallCrawler]

I have the full AFE 3" catback. I just wanted to know if I could get a more aggressive tone. Im not worried about lean issues. I have HP tuners and a tuned truck. that's easy to correct. I was more along the lines of it being a waste of time or money for the outcome.

[lemmuhj]

Would cutting out the resonator be a better option for sound and just leave the third cat?

 

(I replaced stock muffler with a Borla muffler)

[SouthernSilveradoGuy85]

Would cutting out the resonator be a better option for sound and just leave the third cat?

 

(I replaced stock muffler with a Borla muffler)

 

I had everything from the muffler back taken out and didn't touch any of the 3 cats and the sound is awesome and very aggressive. I have a Flowmaster Super 44 single in/dual out and it's the loudest and best sounding truck I've had. I can listen to XM without needing the volume that high even with the windows down (non Bose) while it's loud enough at idle that I can remote start it from my back yard or back end of the house in my bedroom and hear it just fine (I park on the street in front of the house).

Edited November 29, 2014 by SouthernSilveradoGuy85

[07Softail]

I just drilled mine out today and it made no difference whatsoever as far as sound goes. Now screwing the flapper-valve open made more of a difference on the idle sound. Resonator delete is next and if that doesn't do it for me i'm going with a Jones Perforated core muff.

 

RT

Edited January 17, 2015 by 07Softail

[chrislim]

just had mine removed yesterday(little background,I've got a 6.2 with a muffler delete and resonator delete). Sounds a little different on start up but not louder, makes more crackles and pops on decel, where you really notice the difference is up high in the rpm range, it sounds a lot more aggresive

[bgweed]

 

 

 

 

This progression is still a bit unclear to me - how did you manage to get the guts rolled up and pulled out?

just had mine removed yesterday(little background,I've got a 6.2 with a muffler delete and resonator delete). Sounds a little different on start up but not louder, makes more crackles and pops on decel, where you really notice the difference is up high in the rpm range, it sounds a lot more aggresive

 

Did you have the cat gutted or did you have it removed altogether?

[chrislim]

 

This progression is still a bit unclear to me - how did you manage to get the guts rolled up and pulled out?

 

 

Did you have the cat gutted or did you have it removed altogether?

I had it removed

 

 

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[DTOMKIDD]

Will this effect the trucks ability to pass smog In cali? I want to do this but am afraid of having to have a new cat welded in if it fails.

 

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[carkhz316]

I don't know about the rest of you, but here in MN you can scrap Cats and get money. Even a small one like you guys are hacking up is worth $20-30 here. If it were me, I'd just cut it out and turn it in, then section in pipe where you omitted the Cat.

[TJay74]

Will this effect the trucks ability to pass smog In cali? I want to do this but am afraid of having to have a new cat welded in if it fails.

 

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Yes it will affect the ability to pass the California smog test. The whole reason the GM cars have the 3rd cat is for the California smog test. GM used to make 2 sets of each vehicle, 49 state and California. In the recent years they found it was cheaper to make a 50 state car that meets the strictest emission requirements which is the state of California.

[DTOMKIDD]

 

Yes it will affect the ability to pass the California smog test. The whole reason the GM cars have the 3rd cat is for the California smog test. GM used to make 2 sets of each vehicle, 49 state and California. In the recent years they found it was cheaper to make a 50 state car that meets the strictest emission requirements which is the state of California.

I was pretty sure it would fail just thought I'd check, thanks for the help!

 

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[Rkaroll953]

i wonder if id pass CT emissions with it hollowed out. i dont know the process.

[bgweed]

I'm having my truck tuned Saturday... I'm wondering if I should try to do this before I have it tuned. I currently have stock manifolds and cats mated to a Corsa cat back.