Hollowed out cat?

96ZJ · Oct 27, 2005

Ok so I am replacing my trasmission so the exhaust tubing had to come out so I could drop it. Trying to seperate the muffler and the cat I managed to split the muffler open. Soooo since i'm replacing the rear portion of my exhaust system shoud I take the cat off and knock all the crap out of it so its hollow? Will this have an adverse affect on performance? I would get a new cat but I really can't afford the extra $100 for it right now. Having to replace the trans hurt me enough. TIA

-Mike

GoingOffRoading · Oct 27, 2005

96ZJ said:
Ok so I am replacing my trasmission so the exhaust tubing had to come out so I could drop it. Trying to seperate the muffler and the cat I managed to split the muffler open. Soooo since i'm replacing the rear portion of my exhaust system shoud I take the cat off and knock all the crud out of it so its hollow? Will this have an adverse affect on performance? I would get a new cat but I really can't afford the extra $100 for it right now. Having to replace the trans hurt me enough. TIA-Mike

Let me fix this for you

96ZJ said:
This will have an adverse affect on performance. I should reuse the old cat because I really can't afford the extra $100 for it right now. Having to replace the trans hurt me enough. TIA-Mike

On some OBD1 vehicles, running without a cat showed some gains. On ALL OBD2 vehicles, running without a cat will hurt the vehicle (loss of power, millage, etc). In either case, that cat was put there for a reason. If you can afford a trans rebuild, you can afford a 60 dollar OBD2 cat from summitracing.com

Cue-Ball · Oct 27, 2005

The only problem you might run into with hollowing out your cat (other than possibly not passing the sniffer test) is the computer might throw some codes, there is an O2 sensor in the cat that might affect the computer. I am running a Carsounds cat on mine, it is NOT an ODBII compliant cat so we simply drilled a hole and welded in a bung for the O2 sensor, worked out sweet.

I have not need a smog since the work but am sure I will have no trouble.

AW just converted his 5.2 to a 5.9 and hollowed out his cat and the thing runs like a champ, he even passed a smog check here in Cali with a hollowed cat.

So the truth is you will be fine to hollow yours out other than possibly check engine light, but that is doubtfull AW did not get that.

GoingOffRoading · Oct 27, 2005

Cue-Ball said:
AW just converted his 5.2 to a 5.9 and hollowed out his cat and the thing runs like a champ, he even passed a smog check here in Cali with a hollowed cat.

Jerod also has a what... 96 ZJ? 93? Either way he has an OBD1 vehicle.

Cue-Ball · Oct 27, 2005

True AW's is a 93 but you should have no trouble with your 96.

When mine crapped out most of the junk came out and I ran it burnt up for a few weeks back and forth to LA with no trouble until I had a chance to get it replaced.

Bob A · Nov 12, 2005

I'd think that hollowing it out would have the same affect as removing it.I went from 14 down to 12.4 mpg when I removed mine.

AprilzWarrior · Nov 13, 2005

I have a 95 you turds.

96+ OBD II

Cue-Ball · Nov 13, 2005

AprilzWarrior said:
I have a 95 you turds.

96 OBD II

Sorry man I thought it was older. :???:

Hollowed out cat?

96ZJ

GoingOffRoading

Cue-Ball

GoingOffRoading

Cue-Ball

Bob A

AprilzWarrior

Cue-Ball

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