Catalytic Converter Questions

[MrTruck805]

Hi,

The 89 Fullsize 350 Jimmy failed smog today here in California. About 210k miles. I trust the shop I went to, as the guy running the test is an old coworker.

The reason it failed was the emissions were too high at idle (although not by terribly much), but they were ok at the higher RPMs. My plugs and wires are new so he said the main culprit would be the catalytic converter. The one on there looks original to me - although I can see the manufacturer is Hedman - Not sure if they produced cats for GM in the late 80s.

Sounds reasonable enough to just go ahead and get a new cat? Summit is listing a universal fit 2.5" one for about $110 - https://www.summitracing.com/parts/flo-2900225

Seems like a fine price to me. They also have $8 and $28 stainless steel clamps. I'm attaching a two pics of my clamps.... Maybe I can get them off after spraying them with a few rounds of Kroil, or do most people just take the sawzall to them?

Anyway.... seem like a decent enough shot at lowering my idle emmisions? Passing smog isn't so easy here in California.

 

[wetoolowdingbangow]

You cant use universal cats here becuase that would be way too cost efficient lol. it must be model specific. The last one I bought was a walker brand from rock auto...truck passed smog right after that. never hurts to throw an o2 sensor in there too if its shape is unknown.

 

[sweetk30]

you HAVE to make sure its California approved use cat .

and universals tend to last around a year only .

 

[MrTruck805]

You cant use universal cats here becuase that would be way too cost efficient lol. it must be model specific. The last one I bought was a walker brand from rock auto...truck passed smog right after that. never hurts to throw an o2 sensor in there too if its shape is unknown.

Gotcha... I see that same walker cat on Rock Auto... Thanks.... I see that it is CARB compliant. Summit probably won't let me buy that universal one.

 

[skunked]

some universal cats are legal, it's just limited to what applications they can be used on.

I like to use walker when I need CARB approved cats

Direct fit http://www.walkerexhaust.com/catalog/carb-converters/e-catalog-lookup/80942
https://www.summitracing.com/parts/wlk-80942

or

Universal fit http://www.walkerexhaust.com/catalog/carb-converters/e-catalog-lookup/80907
https://www.summitracing.com/parts/wlk-80907

 

[wetoolowdingbangow]

Gotcha... I see that same walker cat on Rock Auto... Thanks.... I see that it is CARB compliant. Summit probably won't let me buy that universal one.

Exactly. ive tried before but once in a blue moon the smog guy will check the numbers. I actually failed a test becuase they couldnt read the cat numbers.

The walker one is bolt on. I think both sides slip over the existing pipes...just need two clamps and its ready to roll.

 

[skunked]

always keep your receipt for the cat in the glove box for the smog nazis

 

[MrTruck805]

Thanks for the replies, Walker cat is ordered!

Anyone have a preference on band clamps, or the ubolt style clamps?

 

[skunked]

I prefer a welder.

 

[scoots90245]

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