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Discussion Starter #1 (Edited)
Gutted my primary cats today

With 115k miles and code P0420 ever present, I decided it was time to gut the front cats.

I unbolted the exhaust from each cat, and slid the pipes back. I used a 2x4 to wedge the pipes up out of the way.

A long screwdriver and a hammer was used to break up the material in the cats. A firm tap on the side of the cats worked well to spit the material out. When nothing else would come out, I used a vacuum to suck out any hidden debris. Last, I cranked the truck up and let it run for a minute, to blow out anything I might have missed. Sucker was loud! :lol: Bolted the exhaust back up and hit the road. Took about an hour for each side.

Before I hit the road, I cleared the code out using my BDGT and monitored my AFR. Before, I was running 12.8 at WOT. I'm running a little leaner at 13.3, but hopefully it will re-adjust over time. So far, the code has not come back. :)

The exhaust is slightly louder at WOT. Otherwise, I can't tell a difference in the exhaust noise level (My exhaust is stock, except for the gutted cats).

As far as power, it pulled good. I'll have to make some 0-60 runs to see if there is an actual improvement.

I'll update this thread later with any change in mileage, and if the code comes back.

Here's a few pics.


This is your Titan's Cat




This is your Titan's Cat after surfing TitanTalk :D



Someone call Al Gore. :teethmast


 

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13.3 AFR is still pretty good. As long as it doesn't go higher than that your good. Although Uprev is worth the money:) I gained .15 when I gutted my front cats along with the rears.
 
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Update? Had an ECU failure 2 mths ago, code won't go away 420 & 430, don't need to worry about emissions testing so I'm thinking of gutting them to get the CEL off
 

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Discussion Starter #4
The codes came back. However, I think using spark plug defoulers to move the O2 sensors out of the stream will stop the codes from coming back. I never got to try it.

Since then, I changed over to headers and Uprev because of the cracked manifolds.
 

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The codes came back. However, I think using spark plug defoulers to move the O2 sensors out of the stream will stop the codes from coming back. I never got to try it.

Since then, I changed over to headers and Uprev because of the cracked manifolds.
Well, best I can tell my manifolds aren't cracked.....plus I plan on just turning the sensors off
 

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u just threw away 120 dollars worth of catalytic converters. thats smart........ should have gone to a mechanic and sold him the cats and welded straight pipes instead.......
 

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arent the primary cats welded to the manifold? no mechanic here will touch the cats or weld straight pipes in place...
 

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Discussion Starter #10
u just threw away 120 dollars worth of catalytic converters. thats smart........ should have gone to a mechanic and sold him the cats and welded straight pipes instead.......
Exhaust shop won't touch anything to do with removing cats.

As far as selling the cats, not worth the hassle. Just to sell copper, the recycle places will take your picture, tag number and so on which are reviewed monthly by the sheriff's office. In addition to the hassle, not worth the risk of being wrongfully accused of stealing.
 

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Discussion Starter #12 (Edited)
Can't say I understand the purpose of all this.

Some folks do it because it's a free mod to gain a little power and sound.

My reason for doing it was to prevent the primary cats from destroying the engine. Up until I started getting a CEL for the cats, I was bone stock. With well over 100k miles, I just felt it was a ticking time bomb so I gutted the cats for peace of mind.

Later, I decided to get headers to replace the cracked manifolds.
 

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Can't say I understand the purpose of all this.
This post is in the performance section, I think it might be for more power. I gained .1 in the 1/4 mile by gutting front cats:)
 

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Some folks do it because it's a free mod to gain a little power and sound.

My reason for doing it was to prevent the primary cats from destroying the engine. Up until I started getting a CEL for the cats, I was bone stock. With well over 100k miles, I just felt it was a ticking time bomb so I gutted the cats for peace of mind.

Later, I decided to get headers to replace the cracked manifolds.
EXACTLY!

I could care less about the CEL codes right now, got some time before I'm due for inspection, BUT since our awesome engines run the risk of sucking parts of the cats baack into the engine, andi don't have $1500+ available to replace everything, this gives the peace of mind.

Oh and screw Gore
 

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No emissions testing in Alabama, so I'm considering doing this.

Also have the cracked manifold. What are the options for headers, and how much does the typical install cost? Heard someone picked up some JBA shorties for around $200.
 

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Discussion Starter #16 (Edited)
If you go with headers, I recommend going with long tubes, because they will bolt right up to your existing pipes.

The $200 JBAs are probably shorty headers, which means some welding will be required to match your exhaust.

The two options for long tubes that are proven are the Doug Thorley and Stillen headers. I bought my DT headers for $588 shipped, and they fit perfect. I think the Stillens may have an issue with the 02 sensor wires not being long enough, so some wire splicing may be required.

I did my own install. If you pay for someone to install headers, expect to pay $400 and up.

If you think you're going to go with headers, I wouldn't bother gutting the primary cats, since the headers will eliminate them.
 

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i just picked up some jba shorties new for 250, so i am re-doing my whole setup now....flanged primary cat elimination pipes headers and a 22'' magnaflow in place of my craptech muffler. 600.00 installed!
 

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What does the law say about this? I love the idea, but isn't it a federal violation? I don't want to be someone's girlfriend because I wanted a 2mpg improvement.
 
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whos gonna tattle?:bangit:
 

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whos gonna tattle?:bangit:
Well I'm not. That's your business.

But I am paranoid enough that I wouldn't post anything about it. But that's neither here nor there because I'm also too chicken to do it with out more information.
 
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