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Discussion Starter · #21 ·
New CAT's installed. Let me just say that "direct fit" doesn't actually mean they bolt up without having to purchase longer bolts (the flanges were welded on the CAT's 1/2" too far forward) and the passenger side the flange was also rotated clockwise about 3/4" so the support bracket no longer works. The CAT's were also 1/2" too short so now my exhaust pipes rattle everywhere. I'm going to a friends house in the morning to see about "clearancing" the exhaust to get rid of the rattles. On the plus side, the original driver side CAT was half plugged and now the car runs much better. I did have to replace the driver side knock sensor pigtail as the insulation on the wiring was bare and wires were all touching each other.
 

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Discussion Starter · #22 · (Edited)
New CAT's installed. Let me just say that "direct fit" doesn't actually mean they bolt up without having to purchase longer bolts (the flanges were welded on the CAT's 1/2" too far forward) and the passenger side the flange was also rotated clockwise about 3/4" so the support bracket no longer works. The CAT's were also 1/2" too short so now my exhaust pipes rattle everywhere. I'm going to a friends house in the morning to see about "clearancing" the exhaust to get rid of the rattles. On the plus side, the original driver side CAT was half plugged and now the car runs much better. I did have to replace the driver side knock sensor pigtail as the insulation on the wiring was bare and wires were all touching each other.
Put my car up on my buddy's lift yesterday and found where the rattles were coming from, some before and after pics.


Not sure why the last 2 pics got rotated and don't know how to fix, sorry guys.
 

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Yeah this crazy California air resources board rules. And I just tried to replace both of my O2 sensors and the right one was cross threaded in. So unless I can find a big enough tap and die set and save the threads I’m going to have to replace that cat. And I’m not going to spend the $1400 that summit racing is looking for to comply with these idiots here in California.
 

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Yeah this crazy California air resources board rules. And I just tried to replace both of my O2 sensors and the right one was cross threaded in. So unless I can find a big enough tap and die set and save the threads I’m going to have to replace that cat. And I’m not going to spend the $1400 that summit racing is looking for to comply with these idiots here in California.
Dude... Just go to an exhaust shop and have them fix it. Aside from repairing the threads, they could also just weld in a new O2 bung. It's a really simple procedure that any decent exhaust shop can handle.

Don't replace a working cat in California just because of some damaged threads.
 

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Dude... Just go to an exhaust shop and have them fix it. Aside from repairing the threads, they could also just weld in a new O2 bung. It's a really simple procedure that any decent exhaust shop can handle.

Don't replace a working cat in California just because of some damaged threads.
As much as I would love to sell a convertor I would have to agree with this. It is very easy for an exhaust shop to replace the bung and a whole crapload cheaper if that is all you need!

Mike--Hamilton Chevy
 

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I think so, here's a pic of the cats I took off recently. The OEM's were shorter, wider, dark titanuim color, didn't have heat shields and didn't have the 02's installed on the cat body. Steve
ARE YOU STILL LOOKING FOR 1996 IMP s/S converters? I have both right and left sides. They have 1,793 miles on them, the car was totaled. Parting out the last of the the serviceable parts and LT- drive train. (GA.]
 

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CA compliant replacement CATS are readily available and are simply welded in. No need to buy the "factory" CAT/Pipe combo. Unfortunately, CA compliant OBD2 CATS are stupid $

Some shops are not cooperative and will only sell/install the 2 1/4" stock pipe size....and others don't care about that point. I have MagnaFlo 2 1/2" OBD2/CARB CATS matching my header collector & exhaust system pipe size.
 
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