Catalytic converters: does your square have them?

Does your square have a catalytic converter?

  • yes

  • no

  • yes, but only because I couldn't get a sticker/plate without them.

  • no, but only because I'm too lazy/cheap to change what the previous owner did.

  • no, because my truck didn't come with them.


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Craig 85

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I remember when I used to have my 65 smogged every 2 years. Was glad when they changed that rule

I remember in June of '84 when smog test stated. The rule then was 20 years and older needed smog. I had the original sales receipt for when my dad purchased the car new in Jan of '64 proving it was over 20 years. The state still made me smog it. They were going to fail it as it needed a Nox kit, but the cost of the kit and install was more than the max repair cost of $50. Never had to worry about it again.
 

Catbox

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461
My truck was built in Canada and it came with a factory cat under it.
Somewhere along the line of it moving from Toronto to Vancouver BC and finally to Oregon the exhaust had been replaced with dual pipes that both have cats in them.
They are the small honeycomb type now.

Since I live in Oregon and they test everything from'76 and up, I will have to put new ones under it when I rebuild the exhaust with headers and all new pipes.
They only perform the visual under the truck to make sure they are still there as well as the sniffer test.
 

Poppy 87

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John
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R10 Silverado
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305
My 87 R10 still has the cat but no muffler. Greater Atlanta requires emission testing back 25 years, part of which is visual inspection. 2012 was the last year my truck needed test
 

80BrownK10

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1980
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K10
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350
My 81 with 350 came with a single pelt type cat back to a muffler and then dual outlets that came out the right side behind the fender. When the warranty was up the whole exhaust from manifolds right to the back was removed and headers with duals installed. All nicely stored in the attic of my garage just in case?? With a distributor recurve and riching the secondary jets mileage went from 7 mpg to 13 mpg while pulling a car hauler trailer loaded.
I'd love to see you pulled ng a loaded car hauler with an 81 square with a 350 getting 13mpg.!!!

I get 8 mpg pulling mine. But I do have 33s and a lift and 4wd
 

80BrownK10

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Here is SC no vehicles are inspected for any reason, smog or otherwise. They got rid of state inspections around about 1996?
 
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Springfield Illinois
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Kevin
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1978
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K10
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350
I'd love to see you pulled ng a loaded car hauler with an 81 square with a 350 getting 13mpg.!!!

I get 8 mpg pulling mine. But I do have 33s and a lift and 4wd
I am so jealous of you guys. Mine wouldn't handle my 28' 10k trailer as it is and I'm getting around 8 mpg not pulling anything.
 

80BrownK10

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I am so jealous of you guys. Mine wouldn't handle my 28' 10k trailer as it is and I'm getting around 8 mpg not pulling anything.
I'm only pulling a 16ft dovetail wood bed car hauler. I probably would have a lot more trouble with that much trailer.
 

PeteJr

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GMC Sierra Classic 1500
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350
My '83 GMC has one, but when I get to the point of switching engines, it'll be left off..........
(I live in Mississippi............ think they worry about pollution? :laughing1:)

If you want to take yours off....... Just park it in Memphis overnight and they will remove it for FREE !

:superhack:
 

HotRodPC

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My 86 C20 came factory with dual exhaust and no cats. No Unleaded Fuel on the fuel guage, and biggo holes for the filler pipes to the tanks. No tiny unleaded flapper fillers. Same as the Diesel fillers I do believe.
 

Ellie Niner

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Yes. After the screen in my original catcon rotted out and let the beads go flying, then an unfortunate backfire blew the muffler wide open, I installed dual exhausts with dual converters. I'm not an enviro-****, but catalysts have proven themselves in improving air quality, and I think it's a good move. I also had a prissy girlfriend who complained a lot about the gassy smelling exhaust when we used to cruise Main with the windows down, and thought I was going to be moving to a place where I'd be getting emissions tests... both of those issues have been rectified, and now those notoriously weak-chested aftermarket cats are starting to get tired... I'll probably replace 'em as funds allow.
 

drware

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My 86 1 ton came with out cats and with dual from factory
Donnie
 

C10MixMaster

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When I was looking to buy a truck of my requirements was a truck that did not come with a cat or EGR from the factory. In 77 the heavy half tons did not have them.
 

SirRobyn0

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Yes. After the screen in my original catcon rotted out and let the beads go flying, then an unfortunate backfire blew the muffler wide open, I installed dual exhausts with dual converters. I'm not an enviro-****, but catalysts have proven themselves in improving air quality, and I think it's a good move. I also had a prissy girlfriend who complained a lot about the gassy smelling exhaust when we used to cruise Main with the windows down, and thought I was going to be moving to a place where I'd be getting emissions tests... both of those issues have been rectified, and now those notoriously weak-chested aftermarket cats are starting to get tired... I'll probably replace 'em as funds allow.
This is exactly my feeling. Also for anyone not aware car exhaust contains NOx, while this gas isn't a long term environmental hazard, it is VERY good at destroying lung tissue on contact. So if your sitting in traffic or rolling down the road and you can smell exhaust you can bet your breathing in at least some NOx more so if your not running a cat. Ask any older mechanic that has developed breathing issues. They'll like know about it.
 
Last edited:

Ellie Niner

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This is exactly my feeling. Also for anyone not aware car exhaust contains NOx, while this gas isn't a long term environmental hazard, it is VERY good at destroying lung tissue on contact. So if your sitting in traffic or rolling down the road and you can smell exhaust you can bet your breathing in at least some NOx more so if your not running a cat. Ask any older mechanic that has developed breathing issues. They'll like know about it.
I'll admit that I get frustrated with emissions controls at times, but taking a look at pictures of the thick smog blanketing heavy industrial areas in places like China and India, then comparing that with ours... sorta reminds you that there is a valid reason for these devices. China and India are kinda like where we were 50 years ago.
 

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