Catalytic Converter - replace CA with 'none' or 'Universal'?

[Roamingdoc]

'02 Tblzr 4WhlDr,(215K) with stock exhaust and CA legal catalytic converter. No longer living in CA and wish to remove the original CATs and "not" toss CELs.

Any experience with this type of 'alteration' here?

I saw the 'spacer' solutions in other threads (use the spk plug anti-fouling spacers to offset the O2 sensors) "BUT" hear (??) that the '02' sensors are oritented differently and can be a bear to 'fit' with the spacers. Anyone?

Appreciate any input or thoughts... plan to use a single exhast 'cat' back with the kitty replaced by a pipe. Thanks!!

 

[DocBrown]

Everything I've ever read or discussed with certified mechanics says you have to stick with CA emmissions standard camapatible parts. If you deviate you have to change out the computer and anything else that's CA emissions standards.

Keep in mind that it is not legal in any state to remove the CAT, though a lot of people do it.

 

[Playsinsnow]

My these 4.2s love a little back pressure to maintain mpgs and low end torque from all the exhaust threads and experiences I have read.

 

[Mounce]

Can I ask what the point of removing them would be? If it's not clogged up and hindering things, I would let it be.

 

[lint]

Glad to see you made it from ''TRAILVOY'' Roamingdog. In PA. You have to keep the cat on to pass inspection so that is why I gutted mine.and still looks stock. And if you live out of the city ,they don't have emissions test. gutting it doesn't change the sound very much'' no drone'' here is the link on how to again .

http://www.evolutionm.net/forums/evo-how-requests-questions-tips/215795-5-o2-cheater-non-fouler-how.html

 

[Roamingdoc]

Hey Thanks for the responses...
There are 'no' inspections in the part of AZ I live in...
But I do want to put on a universal (for instance my 'old' F-150 w/250K still whisper nice had some rusted parts on the CAT... a carefully chosen 'universal' works great, less restriction - also added a less restrictive muffler - still a nice purr... and NO CELs at all ) as this one is the original, long in the tooth (214K) and showing severe signs of 'outside' wear.
Might gut it but leaning towards a good universal CAT.
Thanks again.

 

[jimmyjam]

if you get a pcm tune, they can turn off the "cat efficiency" code. more fool proof than the spacers or whatever

personally I don't like the smell of no cats, i have cats on my aftermarket header ypipe but I have the code shut off so i don't get a CEL just in case

 

[Roamingdoc]

Hey Jim...
Did not know that. I "Had" a PCM tune on the Tblzr but a tranny shop overrode it or 'the car drives' like they did. I am getting my third Tranny... another whole bag of lemons - and so will send the computer in for a 'tuneup' and make sure they do that. Thanks

 

[rocketsound]

I just ordered one of these Walker direct fit converter off Amazon. Through the end of the month there is a $50 rebate on them, making the final cost $95. I just got it today, and it looks good. I'll post back with results after I get it on th truck.

http://www.amazon.com/gp/product/B001AGT7IO/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

 

[Gerbil21]

I just ordered one of these Walker direct fit converter off Amazon. Through the end of the month there is a $50 rebate on them, making the final cost $95. I just got it today, and it looks good. I'll post back with results after I get it on th truck.

http://www.amazon.com/gp/product/B001AGT7IO/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

i just got a magnaflow for $77 from advanced auto with code trt30 for 30% off everything

http://shop.advanceautoparts.com/p/magnaflow-universal-catalytic-converter-99006hm/22315793-P?searchTerm=catalytic+converters

but this is a weld on, $95 is a great price for a bolt on good find

 

[Roamingdoc]

Thanks.... Gerbil...
I think that is a reasonable price... and I need one.

 

[ChrisinVictoria]

I had a plugged converter a year ago. I had a straight pipe welded in and used the spacer on the rear o2 sensor. It does not throw codes and works fine. If I could have purchased a bolt on converter for a hundred bucks I would have gone that route. No inspections where I live.

 

[Gerbil21]

I had a plugged converter a year ago. I had a straight pipe welded in and used the spacer on the rear o2 sensor. It does not throw codes and works fine. If I could have purchased a bolt on converter for a hundred bucks I would have gone that route. No inspections where I live.

Just wondering but How was mpg before and after and how does exhaust smell?

 

[rocketsound]

Maybe gained 1 mpg, but the smell is sickening. and now the exhaust sounds raspy, like a honda with no muffler! Very bad all the way around.

 

[Gerbil21]

Lol you definitely need a new cat then [emoji75]

 

[ChrisinVictoria]

Sorry,
I've been busy lately. It does have exhaust smell but not sulphur. Smells pretty bad when cold. I didn't notice any change in MPG but the wife drives it mostly.

 

[Dammage]

I just acquired an '05 LT EXT with a 5.3 for a song, but I have a feeling I need to replace the Cats as well. Has anyone had an issue with the weld-in Cats, or would you spend the extra cash on the bolt-on setup? If you would go with bolt-on, where is the best place to get them?

Thanks!

 

[Sparky]

My camaro has a gutted cat and smells like an old farm tractor.

If I could weld I'd go that route, but I can't so given I'd have to pay someone else to weld them in might as well go with direct fit. I went with Magnaflow on mine, which I got from Amazon but you could get it wherever.

 

[Dammage]

I just don't know if there is any benefit to using the bolt-on ones other than the convenience factor.

 

[KNBlazer]

I just don't know if there is any benefit to using the bolt-on ones other than the convenience factor.

Here in California, maybe, as the only legal replacement is a bolt on GM CAT... I think NY now also requires GM only CAT, don't remember.... A couple of months ago, I took my nieces car to get smogged and dude looked underneath and jotted down the CARB code on his clipboard...

 

[David11946]

Here in California, maybe, as the only legal replacement is a bolt on GM CAT... I think NY now also requires GM only CAT, don't remember.... A couple of months ago, I took my nieces car to get smogged and dude looked underneath and jotted down the CARB code on his clipboard...

Not to undermine any advice but, Magnaflow makes a California Legal catalytic converter (in both universal and direct fit form) for the Trailblazer/Envoy. I don't believe that there is a necessity to buy the expensive cat converter from GM. Just as long as the part has a C.A.R.B. EO number.

 

[KNBlazer]

Not to undermine any advice but, Magnaflow makes a California Legal catalytic converter (in both universal and direct fit form) for the Trailblazer/Envoy. I don't believe that there is a necessity to buy the expensive cat converter from GM. Just as long as the part has a C.A.R.B. EO number.

I think it's only for the 5.3, unless they recently changed it... go to magnaflow's website and run a search...


update

Checked and nothing for a 4.2 2004 TB, However for a 2003 4.2 there is a CA listing....

 

[rocketsound]

Update: been running the Walker direct fit converter since mid October and have not had check engine light.
Cured the nasty exhaust note and the rotten egg smell. MPG seems un affected with/without converter.

 

[DenaliHD66]

My cat has been rattling and clunking pretty good for several months now. Not looking to spend a whole lot, but would prefer a direct fit cat. Best suggestion? I thought about the Magnaflow high flow ones, but I can't justify it, not on what my vehicle is worth these days.

 

[rocketsound]

My cat has been rattling and clunking pretty good for several months now. Not looking to spend a whole lot, but would prefer a direct fit cat. Best suggestion? I thought about the Magnaflow high flow ones, but I can't justify it, not on what my vehicle is worth these days.

I would recommend the Walker direct fit. I got mine off Amazon, very reasonable price, went on easy. No more check engine light.
http://www.amazon.co...0?ie=UTF8&psc=1

This is the EXT version, won't work on the short wheelbase.

 

[DenaliHD66]

Cool thanks. Has been tough to find parts that advertise as being for the XL as opposed to the regular one.

Does it come with that donut thing?

 

[rocketsound]

No, it did not come with gaskets, I got them from NAPA.