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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RecklessWOT

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For anyone wondering about this there are states that test back into the 70s. In the areas of Oregon that emission testing is done they do it on all vehicles 1976 and newer, no I'm not making that up.
I am aware some states do so, never figured you were making it up. I simply said MOST states, not all. The county my father lives in in Colorado tests all vehicles 1975 and up as well, and we all know California is crazy with the emissions.

But I live about as far away from Oregon as one can get. I don't know of anywhere in the northeast that is so strict, most places around here have an exemption on vehicles over 25 years, if not sooner (as in NHs case where they no longer check anything that's not OBDII, much of Maine does not test any vehicle even new ones), even crazy liberal places like MA and CT.

It is straight up unreasonable to expect a 40 year old vehicle to be reliably be held to the same standard as when it was new, and there are so few of them on the road that the owners are most likely enthusiasts/collectors and the vehicle is not stock to begin with. A couple dirty old cars on the road is not making a difference when the majority of the cars on the road are <15 years old.

I think this is one of the reasons no new vehicle (with maybe a rare exception), has come out in a long time with true duel exhausts, instead you might get single 3" or bigger pipe. It's not uncommon for a V-8 exhaust to come together in Y-pipe, go through the cat, muffler and then split and come out looking like duels.

I'm pretty sure it's done as a cost saving measure, and to save room. Super high end sports cars still have real dual exhaust, as do race cars. But on your average car, even something "sporty" they just make it a single (maybe with dual outlets to look cool) because the advantage isn't large enough to justify having two separate exhaust pipes, two sets of cats, two sets of o2 sensors, making all that extra room underneath the cramped modern cars, etc.

I REALLY doubt they're doing anything to make our exhaust, or anything else for that matter, last longer. The more stuff that needs fixing, the more money they make in replacement parts and repairs. Hence people are always saying "they don't make them like they used to".
 
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Goldie Driver

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If I remember correctly, Texas is 24 years and older for the exemption. Thus the missing cat did not bother me at all.

Not sure how they will work OBD2 cars, though, but if my 24 years is correct in 3 years I can let you know on the Camaro.

It, and the other 3, have all their OE smog stuff.

Not a big greenie when it comes to car emmissions, but few problems so why jack with them.

Plus, its not just the cars - drive thru the chemical plant areas of town and take a whiff.:boxed:

I do try to recycle, though.:)

I hate to see things thrown in a dump that can be reused/repurposed.
 

Frankenchevy

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I am aware some states do so, never figured you were making it up. I simply said MOST states, not all. The county my father lives in in Colorado tests all vehicles 1975 and up as well, and we all know California is crazy with the emissions.

But I live about as far away from Oregon as one can get. I don't know of anywhere in the northeast that is so strict, most places around here have an exemption on vehicles over 25 years, if not sooner (as in NHs case where they no longer check anything that's not OBDII, much of Maine does not test any vehicle even new ones), even crazy liberal places like MA and CT.

It is straight up unreasonable to expect a 40 year old vehicle to be reliably be held to the same standard as when it was new, and there are so few of them on the road that the owners are most likely enthusiasts/collectors and the vehicle is not stock to begin with. A couple dirty old cars on the road is not making a difference when the majority of the cars on the road are <15 years old.



I'm pretty sure it's done as a cost saving measure, and to save room. Super high end sports cars still have real dual exhaust, as do race cars. But on your average car, even something "sporty" they just make it a single (maybe with dual outlets to look cool) because the advantage isn't large enough to justify having two separate exhaust pipes, two sets of cats, two sets of o2 sensors, making all that extra room underneath the cramped modern cars, etc.

I REALLY doubt they're doing anything to make our exhaust, or anything else for that matter, last longer. The more stuff that needs fixing, the more money they make in replacement parts and repairs. Hence people are always saying "they don't make them like they used to".
While I’m not arguing for stricter emissions standards on old vehicles, on the west coast, cars live a lot longer and thus there are many more of them. Every other vehicle that drives by my house is an older pickup truck. Frames don’t really rust apart here.
 

bucket

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Because cats clean up the exhaust, they will help increase exhaust system life. Also getting them up temperature, and on a single exhaust system there is more overall volume of air coming out helping to push moisture and contaminates out. I think this is one of the reasons no new vehicle (with maybe a rare exception), has come out in a long time with true duel exhausts, instead you might get single 3" or bigger pipe. It's not uncommon for a V-8 exhaust to come together in Y-pipe, go through the cat, muffler and then split and come out looking like duels. It also eliminates balance issues associated with a true dual system. This is a real blast to fight by the way, I've had vehicles come in the shop with symptoms similar to having a heat riser stuck closed or partway closed only to find out there is a back pressure difference side to side in the duel exhaust. Simple solve is add a cross over pipe if the difference isn't to extreme.

When you think about the fewer number of older vehicles on the road I doubt if every single square owner cut off his cat that it would amount to anything measurable globally, especially when you consider industrial pollution. But if you live in a city, in particular a city with serious smog issues, like LA, and LA use to be much worse off than they are today reducing the emissions of cars is one of the things that has helped them out.

Most of the GMT800 and later 3/4 and 1 ton trucks actually had dual pipes and dual converters, all the way back to a dual inlet AND outlet muffler. Oddly, the pipes come together right after the muffler and form a single tailpipe. So those ones are backwards- dual exhaust with a single outlet, rather than single exhaust with a dual outlet.
 

idahovette

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From what I've seen exhaust systems are lasting a lot longer than before ,at least in our part of the country. If you check with almost any exhaust shop you see them doing duals or modifications on street rods or muscle cars or offroad rigs, all of them say 15 years or older. They often modify newer catback systems but nothing they replace is bad, the owner is after a sound or looks.
 

gotyourgoat

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Most of the GMT800 and later 3/4 and 1 ton trucks actually had dual pipes and dual converters, all the way back to a dual inlet AND outlet muffler. Oddly, the pipes come together right after the muffler and form a single tailpipe. So those ones are backwards- dual exhaust with a single outlet, rather than single exhaust with a dual outlet.
Interesting, a reverse h-pipe with duals where the gasses are hot and converging where the gasses are cooler. Sounds like it would work good. Guessing clearance issues ultimately created that setup or maybe a bean counter who green lighted the 2 cats but lost it at the price of the 2 tips.

Where is a dyno and a dozen different exhaust setups when you need them?
 

bucket

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Interesting, a reverse h-pipe with duals where the gasses are hot and converging where the gasses are cooler. Sounds like it would work good. Guessing clearance issues ultimately created that setup or maybe a bean counter who green lighted the 2 cats but lost it at the price of the 2 tips.

Where is a dyno and a dozen different exhaust setups when you need them?

I believe it does work well. I'd have to go measure my truck to be sure, but I think it's dual 2.5" pipes that end up as a single 3" tailpipe. I assumed they did it for packaging at the rear of the truck and also because the gasses are cool and the single pipe does fine. It's just the 2-1 immediately after the muffler that baffles me.
 

SirRobyn0

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I believe it does work well. I'd have to go measure my truck to be sure, but I think it's dual 2.5" pipes that end up as a single 3" tailpipe. I assumed they did it for packaging at the rear of the truck and also because the gasses are cool and the single pipe does fine. It's just the 2-1 immediately after the muffler that baffles me.

I'm not really sure if there is a system benefit to it converging into one outlet after the mufflers. Some newer vehicles will converge just before the muffler. The reason in those systems is so they can get the cats closer to the manifold, the closer to the manifold the quicker they warm up and start working at full efficiency. Then they can stick another cat in the pipe just after they converge to clean up anything remaining.
 

SirRobyn0

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I'm pretty sure it's done as a cost saving measure, and to save room. Super high end sports cars still have real dual exhaust, as do race cars. But on your average car, even something "sporty" they just make it a single (maybe with dual outlets to look cool) because the advantage isn't large enough to justify having two separate exhaust pipes, two sets of cats, two sets of o2 sensors, making all that extra room underneath the cramped modern cars, etc.

I REALLY doubt they're doing anything to make our exhaust, or anything else for that matter, last longer. The more stuff that needs fixing, the more money they make in replacement parts and repairs. Hence people are always saying "they don't make them like they used to".

Cost saving possibly a factor, but keep in mind that the the federally mandated 8 year 80,000 mile warranty on emission controls includes stuff like cat converters so manufactures need to make them last at least that long or it will cost them in warranty repairs.
 

SquarebodyGmc

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I have a 1983 GMC K3500 with an auto trans and a 454. The whole exhaust was stripped all I had was the manifold. After multiple muffler shops denied my request to only run mufflers I finally found one that would do it.
In North Carolina. They told me it had to go back to the way it came from the factory to be legal and to pass inspection. However When they were looking up parts and diagrams to redo my exhaust nothing was found for an 83 k3500. I know the 1500 with the 350’s had them. The muffler shop eventually told me that it must have never came with cats. So the truth is I don’t know. But my truck is over 30 years old so it doesn’t need to be inspected. Stupid laws
 

Lefthand6

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If I remember correctly, Texas is 24 years and older for the exemption. Thus the missing cat did not bother me at all.

This is what I thought too. The inspection guy I go to said it depends on the whole antique, classic, or regular plates. I told him my 82 didn't have cats when I purchased it (also the glove box lid is replaced so I don't that list of otpions). He said antique plates are the only ones I could get if a stayed with no cats. Of course he would say this after I had the exhaust redone.
 

Termite_Delight

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Hope this helps you.
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jjester6000

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Mind didn't come with a cat from the factory, but it doesn't even matter anyways since I live in illinois.

I cut the cat off my '95 Subruban, and this state is too broke to care.
 

WesN

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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.
 

82sbshortbed

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No, because I'm too lazy or cheap to replace what the po did.

:lol:

I actually lol at this answer

My answer would be none of the above.

Unless your state makes you have them why would you have them? :shrug:

Mine don't and never will have them.:superhack: :weld:

I don't need no stinking cc
 

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