How many cats and where?

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Slartibartfasr
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Joined: Tue Jan 23, 2024 10:23 am
Year and Trim: 2005 Bonneville GXP

How many cats and where?

Post by Slartibartfasr »

I got a cat underperforming code and would like to know how many cats does an 05 Bonneville GXP have and where are they located. Also how hard to remove? I am familiar with the options. Legal 1 replace 2 clean either with gas additive or removal and soaking. Not legal but not obvious to the casual observer so will pass state inspection most of the time. 1. O2 spacer 2. Gut the cats and 02 spacer. Totally illegal and will fail state inspection without accompanying case of beer, and even then probably not. Cat delete.

Of course the only options anyone should consider are the cleaning or replacement. That is why I would like to know where they are and how hard to remove ( and replace). Thanks
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harofreak00
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Year and Trim: 2004 GXP - plus a handful of other Bonnevilles
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Re: How many cats and where?

Post by harofreak00 »

1 cat, mounted at the bottom of the downpipe. It has a rectangular flange on the front side with 4 bolts. It's pretty easy to see if you just look under the car. The rear of the cat must be welded in if you're getting it replaced.

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Slartibartfasr
SE Member
SE Member
Posts: 12
Joined: Tue Jan 23, 2024 10:23 am
Year and Trim: 2005 Bonneville GXP

Re: How many cats and where?

Post by Slartibartfasr »

harofreak00 wrote:1 cat, mounted at the bottom of the downpipe. It has a rectangular flange on the front side with 4 bolts. It's pretty easy to see if you just look under the car. The rear of the cat must be welded in if you're getting it replaced.

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Thanks. Just got the car and have not had a chance to put it up on ramps to look at it.
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