Deleting the Catalytic Converter

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Mango

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Hey All
I still have the original Cat on my 89 Burb 350 188.000 miles what happens if I take it off? Back pressure issues? MILPG? No Emissions in Wyoming

Thanks
 

CalSgt

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Theres no O2 sensor after the cat, won't cause any issue to remove it. You could also probably get in there & chip out the inside rather than cutting it out.

Is it busted? Rattling? Plugged up?

If you can pull a grade at full throttle it's not plugged.

I say leave it alone unless its busted or plugged up. Exhaust fumes are so much more tolerable with a working cat, especially when stopped idling in a drive through or stop light.
 

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Scroll down a few lines on this forum and read the thread "Bringing the cat back.... enough is enough".
 

Radiohead

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Hey All
I still have the original Cat on my 89 Burb 350 188.000 miles what happens if I take it off? Back pressure issues? MILPG? No Emissions in Wyoming

Thanks
What happens? You stink like unburned hydrocarbons. Your eyes water and it smells like 1972 all over again.

If it's not broken, don't "fix" it.
 

bucket

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Imho, the factory cats still used on the GM trucks in '89 are all "broken". They are the restrictive, pellet type.

Cut that garbage off of there and put a modern type of cat in it's place. Best of both worlds, no power robbing and a cleaner exhaust.
 

BRetty

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I'm thinking of "stealing" my own catalytic converters. I drive a '73 in California, no idea why the PO had cats on it, I have dark suspicions I won't air in a public forum.

My Exhaust is a F***ing mess, has broken on the highway causing fountains of sparks, the worst welding I have ever seen. I have almost all the parts now to replace it,, just no lift.

To be Continued......
 

mibars

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It will smell bad, give headaches to some but will untap a bit of power. I'd put a universal metal core cat instead. I used a Magnaflow cat converter in all my cars, worked well in 240 HP oil burning Honda, cutting all the smell and most of the smoke with no noticeable effect on power.
 

BRetty

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I rejoice in the fact I could run straight headers with no mufflers at all and it would still be legal in KaliforniaStan. I know nothing about exhaust work, but my current plan is:

Replace crappy '83 exhaust manifolds with Doug Thorley Tri-y headers I got off CList
Headers --> 2.5" bolt-on header/reducers
Reducers --> 12" 2.5"dia flex pipes
Flex pipes --> 2.5" Summit Racing X-pipe assembly
X-pipe-assembly --> 2.5"/2.25" reducer(s)
Reducers --> existing 2.25" generic mufflers and existing tailpipes

I have all sorts of exhaust leaks and horrible noises coming from under my truck. I need to replace the exhaust and at least this will eliminate some potential sources of noise so I can know if my driveshaft is farked.

B
 

SquareRoot

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I rejoice in the fact I could run straight headers with no mufflers at all and it would still be legal in KaliforniaStan. I know nothing about exhaust work, but my current plan is:

Replace crappy '83 exhaust manifolds with Doug Thorley Tri-y headers I got off CList
Headers --> 2.5" bolt-on header/reducers
Reducers --> 12" 2.5"dia flex pipes
Flex pipes --> 2.5" Summit Racing X-pipe assembly
X-pipe-assembly --> 2.5"/2.25" reducer(s)
Reducers --> existing 2.25" generic mufflers and existing tailpipes

I have all sorts of exhaust leaks and horrible noises coming from under my truck. I need to replace the exhaust and at least this will eliminate some potential sources of noise so I can know if my driveshaft is farked.

B
Well then rejoice and get r done.
 

Strick

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With all the Tamper Laws & Federal Mandates associated with converters, I wouldn't post ANY intention or mention of what plans I had for it. ICE engines ran for close to 100 years without them...so...

Strickland
 

Rusty Nail

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What will happen? It WILL stink and make you nauseous, you will hate it. Huge turnoff for anyone near your truck, needless to say it's 100% illegal. Certainly will NOT turn your Suburban into a racing truck..:nono:

Again, you will hate it.

A new one is a good idea, technology has come a long way. You can buy aftermarket from your muffler shop OR
Jeg's sells a Flowmaster brand for a measly $150.

@ www.jegs.com
You must be registered for see images attach


Did I mention the part about you would hate it? It's truuuuuuuuuue!
Truuuuuuuuuuuuue!!
 
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WFO

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What will happen? It WILL stink and make you nauseous, you will hate it. Huge turnoff for anyone near your truck, needless to say it's 100% illegal. Certainly will NOT turn your Suburban into a racing truck..:nono:

Again, you will hate it.

A new one is a good idea, technology has come a long way. You can buy aftermarket from your muffler shop OR
Jeg's sells a Flowmaster brand for a measly $150.

@ www.jegs.com
You must be registered for see images attach


Did I mention the part about you would hate it? It's truuuuuuuuuue!
Truuuuuuuuuuuuue!!
Mine is an 86 with the C6P option, so it came from the factory without cats, even has the large fuel fill opening for leaded gas.
I don't hate it. People around it don't hate it, and no one has gotten gotten nauseous.
Same thing with my 69 Chevelle.
 

mlsceo

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Mine is a 77 long bed. Though I still have to do smog checks it came stock without a cat due to the 6050 GVWR. I went with dual 2 1/2" exhaust with 40 series Flowmasters, H pipe, and side exits. Doesn't stink or offend anyone and sounds amazing.
 

84C20HD

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I own two Canadian built 1984 C20 and a C30. The C20 came with a convertor and the C30 without. When I get around to getting the C30 on the road it will have a convertor on it. NOBODY likes driving behind a SKUNK !
 

Rusty Nail

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Oh boy oh boy! Hot rod racing Suburban here we come!!

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